Comprehensive assessment for motor and visually impaired people using a hierarchical model Awais Ahmad Khan, Ghassan Ali Kbar & Naveed Ahmad Universal Access in the Information Society International Journal ISSN 1615-5289 Volume 17 Number 1 Univ Access Inf Soc (2018) 17:147-160 DOI 10.1007/s10209-017-0523-2 1 23 Your article is protected by copyright and all rights are held exclusively by SpringerVerlag Berlin Heidelberg. This e-offprint is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com”. 1 23 Author's personal copy Univ Access Inf Soc (2018) 17:147–160 https://doi.org/10.1007/s10209-017-0523-2 LONG PAPER Comprehensive assessment for motor and visually impaired people using a hierarchical model Awais Ahmad Khan1 • Ghassan Ali Kbar2 • Naveed Ahmad3,4 Published online: 6 February 2017 Springer-Verlag Berlin Heidelberg 2017 Abstract The evolution of various modern technologies has inspired researchers to assess the effectiveness of these technologies for people with diversified disabilities. In this article, a comprehensive and effective assessment method for motor and visually impaired people has been accomplished using analytical hierarchy process (AHP). In the first phase, the proposed evaluation is based on the comparative judgment of the clinical experts using the AHP rating scale. In the second phase, the evaluation is authenticated by incorporating user judgment scores based on multi-weighted scoring model (MWSM). The MWSM output values are then converted to the AHP scale. The AHP algorithm is applied on the basis of average scores obtained from both evaluations. The technique successfully explores the essential, supporting and optional technologies for various people with disabilities (PwD) as well as identifying the criteria weight used for assessing research articles and existing solutions. Moreover, the assessment criteria are used by MWSM to assess research papers Electronic supplementary material The online version of this article (doi:10.1007/s10209-017-0523-2) contains supplementary material, which is available to authorized users. & Awais Ahmad Khan awais78@gmail.com 1 Mechanical Engineering Department, University of Engineering and Technology, Lahore, Pakistan 2 Riyadh Techno Valley, King Saud University, Riyadh, Saudi Arabia 3 Industrial and Manufacturing Engineering Department, University of Engineering and Technology, Lahore, Pakistan 4 Princess Fatima Alnijiris’s Research Chair for Advanced Manufacturing Technology (FARCAMT), King Saud University, Riyadh, Saudi Arabia related to motor and visual impairment conditions. The assessment techniques have successfully identified the relevant criteria that can be used to assess technological research papers. It also reports the suitability of the various technological solutions and explores the limitations of the designed technological solutions for PwDs. Keywords Motor and visual impairment AHP MWSM People with disabilities 1 Introduction Analytical hierarchy process (AHP) is a decision-making method used for selection and grading of various alternatives by comparison. Since it can use qualitative data (expert opinions), it found its way to several sectors such as industrial, social, educational and financial. Phillison [1] has developed a program which uses multicriteria optimization theory for rapid prototyping machine selection. The program uses three factors, i.e., time, cost and quality to be reduced to single function. Pareto-optimal solutions are used to solve the multi-objective conflicting problem. Pham and Gault [2] compared the rapid prototyping technologies available at that time. They have presented the strengths and weaknesses of the technologies used. In addition, the authors have presented a primary guide for layered manufacturing processes selection through a flowchart. Vaidya and Kumar [3] showed a wide spectrum of AHP applications such as maintenance, performance evaluation, decision making, source allocation and other fields. Hanumaiah et al. [4, 5] have developed an excellent quality function deployment–analytical hierarchy process (QFD– AHP) model for rapid hard tooling selection. The model 123 Author's personal copy 148 consists of two steps: criteria prioritization using the AHP method, and identifying the critical process parameters using QFD. The output of AHP is used as input in the QFD. This research has been extended by using fuzzy AHP for manufacturability evaluation. Lee and Kwak [6] presented an application of AHP for health care. The authors presented a case study to plan the information resource in a healthcare system. The main objective was to design and evaluate a model for effective planning of the healthcare system. Singpurwalla et al. [7] proposed the use of AHP as a tool to facilitate decision making of two specific healthcare populations. The authors used AHP to improve physician–patient communication by assisting shared health decision and helped the patients to evaluate and understand their healthcare options rather than relying completely on the doctors decision. Forgionne and Kohli [8] used AHP to evaluate the quality of journals, with a methodology for consolidating multiple criteria into an integrated measure of journal quality, with discussion on data collection process. Tadisinaet al. [9] discussed the application of the analytical hierarchy process (AHP) to the selection of a doctoral program. The developed hierarchy discussed four criteria which can be examined with four different perspectives to evaluate different doctoral programs. Byun [10] proposed a decision-making method for selecting the best passenger car models through combining AHP and a spreadsheet model. The consistency ratio is used as the decision-makers weights. Kahraman et al. [11] proposed a fuzzy AHP approach for the evaluation of catering firms and the selection of the best location for a facility. Chang and Lo [12] applied an integrated analytical hierarchy process–genetic algorithm (AHP–GA) approach to deal with the job shop scheduling problem. The scheduling sequence is established by an AHP model using qualitative data. The AHP method can be applied for assessing assistive technology (AT) solutions by identifying and ranking the criteria used in the evaluation. The development of AT is not about accommodating the person to the technology, rather it aims to meet and satisfy the needs of the user. Similar to the universal design and development process, the assessment of the AT outcome is also very crucial to eventually achieve customer satisfaction. Although the assessment of the AT outcomes and their economic significance has been an important issue, still comparatively little attention has been given to it [13]. Note that the analysis of the AT system in terms of its effectiveness is crucial to satisfy the end users (PwDs) as well as encourage the investors for their participation in this noble work. There has been a consensus among the stakeholders that the AT field does need a reliable and valid measure to determine the impact of AT systems [14]. The assessment 123 Univ Access Inf Soc (2018) 17:147–160 of the AT outcome can be defined as an investigation process to determine the effect of the AT in the lives of the users and their environments [15]. Although a lot of qualitative methods are described in the literature, there is shortage of translating qualitative data into well-structured quantitative form. The EuroCol [16] and MWSM [17] techniques use both qualitative and quantitative assessment measurement which helps in determining more accurately the performance or outcomes using numerical results. However, EuroCol unlike MWSM cannot be used for assessing solutions that support modality. The MWSM technique involves users when determining the weight of the performance criteria and still requires usability test to validate the final solution in order to get user feedback about the performance of the solutions under assessment. The assessment criteria used in the MWSM technique [17] have been defined through expert opinion and cross-checked with users, however, without considering the autocorrelation among the different criteria. For this reason, multiple models are considered in this article for comprehensive assessment of various technologies among PwDs and by using well-defined criteria that consider simultaneously the opinions of experts and users as well as considering the correlation effect of these criteria. 2 Assessment models The assessment models considered three kinds of impairment groups, namely partial motor impairment, full motor impairment and partial visual motor impairments. The qualitative assessment approach is used to identify the applicability of the different proposed technological solutions in addressing the needs of PwDs. Thirteen technologies have been shortlisted by reviewing the relevant literature [17] and also presented in Table 1. It can be observed in Table 1 that a person with disability has to send signals to the computer system using technologies, namely T1, T2, T3, T4, T5, and receive signal/messages from the computer systems using technologies such as T6, T7, T8, T9, T10 and T11. The other technologies (T12, T13) are used to support the computer processing and improving the signal quality. Two types of assessment models are used in this study. The AHP scale is used to gather qualitative data from experts, and MWSM is used to assess users’ rating. The reason of using AHP scale is that the experts are assumed to be well aware of usability of these technologies and they can rate them easily according to the requirements of PwD. It might be difficult for the users to rate on this scale because of their lack of knowledge about all technologies. Therefore, it would be more appropriate for the users to Author's personal copy Univ Access Inf Soc (2018) 17:147–160 149 Table 1 Relevant technologies Technologies Explanation Relevance to PwD T1 Speech to text Helps others to communicate with PwD and helps in controlling interfaces T2 Keyboard or touch screen or remote Helps to enter messages and control interfaces T3 Gesture control using sensor or camera Helps to observe the environment T4 Tracking location using sensors or WIFI or RFID Helps in determining location of PwD for decision making T5 Sensors for behavior Helps in tracking PwD movement T6 Text or digital mapping to speech Helps PwD to communicate with others people T7 Magnification of font and window size Helps in reading messages and seeing pictures T8 Color control Helps in seeing frames and interfaces T9 Display system Helps interacting with systems T10 Auto-adjustable speaker and volume control Helps with hearing and speaking T11 T12 Haptic or vibration or flashing Mobile support Helps with sensory interfaces Helps in carrying smart systems for interfacing with the environment T13 Noise filtering Improves hearing quality Table 2 Performance criteria used for assessing technologies for PwD Criterion Importance rating Additive Weight Ct1: Not needed (does not affect functionality) 1 1/10 10% Ct2: Less important (slightly improve functionality) 2 2/10 20% Ct3: Important (improve functionality) 3 3/10 30% Ct4: Critical (depends on it, without it cannot function) 4 4/10 Total answer in yes/no/may be format, and hence, a MWSM is used to assess the user’s rating. Afterward, the MWSM rating would be converted into AHP scale for compatibility. All the technology ratings were performed by the authors and workgroup committee. In order to ensure that the ratings are consistent with the needs of PwD, the committee consulted with experts who have specialized in accessibility for PwD for more than 20 years. For user ratings, the committee conducted a survey with the target stakeholders (PwD), and the results are described in Appendix-A (Supplementary material: File name ‘‘SuppMI-PwDsurvey’’). 2.1 Applying MWSM for user rating The MWSM model used to access technological criteria can be performed using the following two basic steps. Step 1 Identify the assessment criteria and their weight The performance criteria (Ctx) are identified to assess the relevant technologies which can satisfy the different impairment conditions. As shown in Table 2, the Ctx is rated according to the importance level of the technologies and is a function of their application. Note that the total 40% 100% additive weight for all the criteria (Ctx) should be equal to 1. Step 2 Assessment of technologies using MWSM The mechanism of MWSM is applied to determine the scores based on the technology performance criteria (Ct1– Ct4) for technologies applicable to partial motor impairment P.MI, full motor impairment F.MI and partial visual motor impairment P.VMI. Note that the following assumptions are considered for the evaluation of the technology score: critical: yes = 10, may be = 5, no = 0; important: yes = 10, may be = 5, no = 0; less important: yes = 10, may be = 5, no = 0; not needed: yes = 10, may be = 5, no = 0). To calculate the average weight of a technology, each technology was given a rating of 0, 5 or 10 points for each of the different criterions Ct1–Ct4. Since the severity of a disability is different from one person to another, PwDs rated technologies differently. For example, T1 in Table 3 was rated 10, 5, 5 and 0 for criterion Ct4, Ct3, Ct2 and Ct1, respectively. This means that some PwD thought T1 is critical for them, so they rated it with 10 on Ct4, while others rated it with 5 on Ct3 because they thought it might be important to them. However, no PwD thought that T1 is not needed, so it was rated 0 on Ct1. As shown in Table 3, 123 Author's personal copy 150 Univ Access Inf Soc (2018) 17:147–160 Table 3 Assessing input technologies for P.MI using performance criteria (Ctx) defined in step 1 Criterion Weight (W) T1 (speech to text) T2 (keyboard or touch screen or remote) T3 (gesture control using sensor or camera) T4 (tracking location using sensors, WiFi, RFID) T5 (sensors for behavior) Rating (R) R WXR R WXR R WXR R WXR WXR Partial MI (computer system input technology) Ct1 10% 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Ct2 20% 5.0 1.0 5.0 1.0 5.0 1.0 5.0 1.0 5.0 1.0 Ct3 30% 5.0 1.50 5.0 1.5 5.0 1.5 10.0 3.0 5.0 1.5 Ct4 40% 10.0 4.0 5.0 2.0 10.0 4.0 5.0 2.0 5.0 2.0 Total 6.5 4.5 6.5 the rating of different technologies is calculated using the 4 P Rji Wji . For example, Rji for T1 ¼ MWSM equation i¼1 ½0; 5; 5; 10 and Wji ¼ ½0:1; 0:2; 0:3; 0:4. Then 4 P R1i i¼1 W1i ¼ 6:5: The rating of the 13 technologies that were assessed by users is presented in Appendix-B (Supplementary material: File name ‘‘SuppMI-PwDWeight’’). 2.2 Analytical hierarchy process 2. 3. 4. 5. 6. AHP is an efficient and most widely used multi-criteria decision-making tool that can use qualitative data as expert or user opinion and synthesize it in the form of numeric weights. This is an eigenvalue approach to the pairwise comparisons. The process is elaborated in the steps described in the following. Step 1 Identify the scale for assessing the technologies AHP provides a methodology [3] to calibrate the numeric scale for the measurement of quantitative as well as qualitative performances. The scale ranges from 1 to 9, for ‘least valued than,’ to 1 for ‘equal,’ and to 9 for ‘absolutely more important than’ covering the entire spectrum of the comparison. The AHP scale is presented in Table 4. The analytical hierarchy model consists of three main activities, namely hierarchy construction, priority analysis and consistency verification. The overall procedure of the AHP is elaborated in the following steps: Table 4 AHP scale Scale 1 Equal importance 3 Less importance 5 7 Moderate importance Strong importance 9 Extreme importance 2,4,6,8 Intermediate values 123 1. 6.0 4.5 Breakdown the complex multiple criteria decision problems into their component parts; Arrange every possible attributes into multiple hierarchical levels; Make pairwise comparisons in the same level with respect to the corresponding criteria in the previous level; Establish priorities among the elements in the hierarchy; Synthesize judgments (to obtain the set of overall or weights for achieving your goal); Evaluate and check the consistency of judgments. Since the comparisons are carried out through personal or subjective judgments, some degree of inconsistency may be occurred. To guarantee the judgments are consistent, the final operation, i.e. consistency verification, which is regarded as one of the biggest advantages of AHP, is incorporated in order to measure the degree of consistency among the pairwise comparisons by computing the consistency ratio. If the consistency ratio exceeds the limit, the decision makers should review and revise the pairwise comparisons. Once all pairwise comparisons are carried out at every level and are proved to be consistent, the judgments can then be synthesized to find out the priority ranking of each criterion and its attributes [18]. The complete AHP procedure is shown in Fig. 1. Step 2 Assessment of technologies using AHP In the AHP model, each disability is considered to be equally important. Therefore, in the first hierarchy, the relative importance (weight) for each impairment group is {0.33, 0.33, 0.33}. The complete assessment model for the current problem is shown in Fig. 2. In the first step, a pairwise matrix that is constructed on the basis of relative importance of each technology depends on average scores of expert and user ratings. The experts and user score data for each technology are obtained from the survey results. Each technology priority/weight is evaluated in a pairwise comparison fashion. The advantage of using the AHP model is that not only those technologies are being assessed Author's personal copy Univ Access Inf Soc (2018) 17:147–160 151 Step 1 For a pairwise matrix 2 3 C11 C12 C13 4 C21 C22 C23 5 C31 C32 C33 Develop a multi-attribute hierarchical model Step 2 Sum of the column values n X Cij Cij ¼ Construct the pairwise comparison matrix for the attributes i¼1 Step 3 Divide each element in the matrix by its column total 2 3 X11 X12 X13 Cij Xij ¼ Pn ¼ 4 X21 X22 X23 5 i¼1 Cij X31 X32 X33 Establish priorities among attributes Step 4 Divide the sum of normalized column of matrix by the number of criteria used (n) to generate weighted matrix 2 3 Pn W11 j¼1 Xij ¼ 4 W12 5 Wij ¼ n W13 Synthesize Judgment Check consistency If consistency within the limit No Yes Rank Judgment Fig. 1 Analytical hierarchy process separately for each impairment group but also their relative importance is established. The degree of consistency among the pairwise comparison is evaluated by computing the consistency ratio. The AHP algorithm is described in the following: Pairwise matrices are presented here along with their calculated priority vectors/weights for each technology separately for PMI, FMI and PVMI. The ranking of each technology was first obtained on the basis of their importance by experts using the AHP scale (Table 4). Then, these technologies were ranked again by user survey scores using MWSM (Table 3). Afterward, the average values of these two scores were taken and listed on the AHP scale. This scale is used for obtaining the relative importance of these technologies. For example, technology T5 in PMI group is very important according to expert opinion with a score 7 (Table 4) though the user score for this technology is smaller. Therefore, by taking the average of these two scores, T5 will come out as moderate important technology with a score of 5 on AHP scale (Table 4). Now, the pairwise comparison matrix is constructed by checking the relative importance of each technology with respect to each other. For example, technology T1 has a score of 8 and technology T5 has 6 in PMI; therefore, technology T5 has ranked as 3 when comparing with T1 and technology T1 has a score of 1/3 (0.33) compared to T5 (Table 5). When comparing the same technologies such as T1 with T1 or different technologies with the same scores like T1 with T6, they are ranked as 1 (equal importance on AHP scale). The pairwise comparison matrix is obtained in this way for all the technologies with each impairment group as listed in Tables 5, 6 and 7. Moreover, weight with respect to each impairment group will be calculated by applying the above algorithm from step 1 to step 4. It can be observed from Tables 5, 6 123 Author's personal copy 152 Univ Access Inf Soc (2018) 17:147–160 Assessment Criteria PMI T1 T2 FMI T3 T4 T5 T6 T7 PVMI T9 T8 T10 T11 T12 T13 Fig. 2 Developed AHP model and 7 that few technologies, such asT1, T3 and T6 for PMI, T1, T6 for FMI and PVMI, have equal weight because of their equal importance at the AHP scale. The output data are presented in Tables 5, 6 and 7. The appropriate consistency index is called random consistency index (R1). Satty [19] proposed the index by randomly generated reciprocal matrix using scale 1/9, 1/8, …, 1, …, 8, 9 (similar to the idea of Bootstrap) and get the random consistency index to see whether it is about 10% or less. If the consistency levels are greater than or equal to 10%, then you have to do your survey again. The following steps are applied to ascertain the judgment consistency for each impairment group. Step 5 Consistency vector is generated by multiplying pairwise matrix by the weight vector: 2 32 3 2 3 C11 C12 C13 W11 Cv11 4 C21 C22 C23 54 W12 5 ¼ 4 Cv12 5 C31 C32 C33 W13 Cv13 Step 6 k is calculated by averaging the value of consistency vector: k¼ n X Cvij : i¼1 123 Step 7 Consistency index (measure of diversion) is calculated by c1 ¼ kn : n1 Step 8 Cr \ 0.1 is set as threshold value to check the inconsistencies in the judgment by Satty [19] Cr ¼ C1 : R1 The consistency of the evaluation is validated for each impairment group separately by applying step 5–8 of the algorithm. The data are presented in Table 8. The importance of each technology on the basis of their weight is also presented in Fig. 3. On the basis of their weight, the technologies are classified as essential (Wt C 0.08), supporting (0.04 B Wt \ 0.08) and optional (Wt \ 0.04), as shown in Table 9 (percentage of essential technologies). Table 9 presents the total score of essential technologies needed for each disability in order to satisfy the requirements of users with disabilities and determine how well particular technologies justify the essential conditions of that group. The percentage of supporting technologies presents a total score of the supporting technologies needed for these impairment groups. These Author's personal copy Univ Access Inf Soc (2018) 17:147–160 153 Table 5 Weight/priority vector for PMI P.MI T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 Weights T1 1.00 2.00 1.00 1.00 3.00 1.00 4.00 5.00 1.00 2.00 2.00 1.00 4.00 0.12 T2 0.50 1.00 0.50 0.50 2.00 0.50 3.00 4.00 0.50 1.00 1.00 0.50 3.00 0.07 T3 1.00 2.00 1.00 1.00 3.00 1.00 4.00 5.00 1.00 2.00 2.00 1.00 4.00 0.12 T4 1.00 2.00 1.00 1.00 3.00 1.00 4.00 5.00 1.00 2.00 2.00 1.00 4.00 0.12 T5 0.33 0.50 0.33 0.33 1.00 0.33 2.00 3.00 0.33 0.50 0.50 0.33 2.00 0.04 T6 1.00 2.00 1.00 1.00 3.00 1.00 4.00 5.00 1.00 2.00 2.00 1.00 4.00 0.12 T7 0.25 0.33 0.25 0.25 0.50 0.25 1.00 2.00 0.25 0.33 0.33 0.25 1.00 0.03 T8 0.20 0.25 0.20 0.20 0.33 0.20 0.50 1.00 0.20 0.25 0.25 0.20 0.50 0.02 T9 1.00 2.00 1.00 1.00 3.00 1.00 4.00 5.00 1.00 2.00 2.00 1.00 4.00 0.12 T10 0.50 1.00 0.50 0.50 2.00 0.50 3.00 4.00 0.50 1.00 1.00 0.50 3.00 0.07 T11 T12 0.50 1.00 1.00 2.00 0.50 1.00 0.50 1.00 2.00 3.00 0.50 1.00 3.00 4.00 4.00 5.00 0.50 1.00 1.00 2.00 1.00 2.00 0.50 1.00 3.00 4.00 0.07 0.12 T13 0.25 0.33 0.25 0.25 0.50 0.25 1.00 2.00 0.25 0.33 0.33 0.25 1.00 0.03 Table 6 Weight/priority vector for FMI F.MI T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 Weights T1 1.00 7.00 2.00 2.00 4.00 1.00 6.00 6.00 2.00 2.00 3.00 5.00 5.00 0.17 T2 0.14 1.00 0.17 0.17 0.25 0.14 0.50 0.50 0.17 0.17 0.20 0.33 0.33 0.02 T3 0.50 6.00 1.00 1.00 3.00 0.50 5.00 5.00 1.00 1.00 2.00 4.00 4.00 0.11 T4 0.50 6.00 1.00 1.00 3.00 0.50 5.00 5.00 1.00 1.00 2.00 4.00 4.00 0.11 T5 0.25 4.00 0.33 0.33 1.00 0.25 3.00 3.00 0.33 0.33 0.50 2.00 2.00 0.05 T6 T7 1.00 0.17 7.00 2.00 2.00 0.20 2.00 0.20 4.00 0.33 1.00 0.17 6.00 1.00 6.00 1.00 2.00 0.20 2.00 0.20 3.00 0.25 5.00 0.50 5.00 0.50 0.17 0.02 T8 0.17 2.00 0.20 0.20 0.33 0.17 1.00 1.00 0.20 0.20 0.25 0.50 0.50 0.02 T9 0.50 6.00 1.00 1.00 3.00 0.50 5.00 5.00 1.00 1.00 2.00 4.00 4.00 0.11 T10 0.50 6.00 1.00 1.00 3.00 0.50 5.00 5.00 1.00 1.00 2.00 4.00 4.00 0.11 T11 0.33 5.00 0.50 0.50 2.00 0.33 4.00 4.00 0.50 0.50 1.00 3.00 3.00 0.07 T12 0.20 3.00 0.25 0.25 0.50 0.20 2.00 2.00 0.25 0.25 0.33 1.00 1.00 0.03 T13 0.20 3.00 0.25 0.25 0.50 0.20 2.00 2.00 0.25 0.25 0.33 1.00 1.00 0.03 Table 7 Weight/priority vector for PVMI P.VMI T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 Weights T1 1.00 4.00 2.00 4.00 4.00 1.00 2.00 2.00 2.00 2.00 3.00 2.00 4.00 0.15 T2 0.25 1.00 0.33 1.00 1.00 0.25 0.33 0.33 0.33 0.33 0.50 0.33 1.00 0.03 T3 0.50 3.00 1.00 3.00 3.00 0.50 1.00 1.00 1.00 1.00 2.00 1.00 3.00 0.09 T4 0.25 1.00 0.33 1.00 1.00 0.25 0.33 0.33 0.33 0.33 0.50 0.33 1.00 0.03 T5 0.25 1.00 0.33 1.00 1.00 0.25 0.33 0.33 0.33 0.33 0.50 0.33 1.00 0.03 T6 1.00 4.00 2.00 4.00 4.00 1.00 2.00 2.00 2.00 2.00 3.00 2.00 4.00 0.15 T7 0.50 3.00 1.00 3.00 3.00 0.50 1.00 1.00 1.00 1.00 2.00 1.00 3.00 0.09 T8 0.50 3.00 1.00 3.00 3.00 0.50 1.00 1.00 1.00 1.00 2.00 1.00 3.00 0.09 T9 0.50 3.00 1.00 3.00 3.00 0.50 1.00 1.00 1.00 1.00 2.00 1.00 3.00 0.09 T10 0.50 3.00 1.00 3.00 3.00 0.50 1.00 1.00 1.00 1.00 2.00 1.00 3.00 0.09 T11 0.33 2.00 0.50 2.00 2.00 0.33 0.50 0.50 0.50 0.50 1.00 0.50 2.00 0.05 T12 0.50 3.00 1.00 3.00 3.00 0.50 1.00 1.00 1.00 1.00 2.00 1.00 3.00 0.09 T13 0.25 1.00 0.33 1.00 1.00 0.25 0.33 0.33 0.33 0.33 0.50 0.33 1.00 0.03 123 Author's personal copy 154 Univ Access Inf Soc (2018) 17:147–160 supporting technologies assist in determining how well a particular impairment satisfies the less important conditions of that group. The percentage of optional technologies, which presents a total score of the optional technologies, can be dropped for these impairment groups. It can be observed in this figure that the technologies T1, T3, T6 and T9 are essential for all MI groups, whereas technology T4 is essential for P.MI and F.MI, T10 is for F.MI and P.VMI and T12 is essential to P.MI and P.VMI only. Another advantage of using AHP is the determination of overall ranking/weight for each technology. The overall ranking/weight will be calculated by matrix multiplication of weight columns in Tables 5, 6 and 7 with impairment group weight, i.e., {0.33, 0.33, 0.33}. On the basis of these results, the technologies can be classified as essential (Wt C 8%), supporting (4% B Wt \ 8%) and optional (Wt. \ 4%). The significance of having these ranking/weight is the shortlisting of technologies with respect to diversified disabilities. The overall weight as percentage for P.MI, F.MI and P.VMI can be seen in Table 10. Again, the classification of these technologies on the basis of total percentage is listed in Table 11 and Table 8 Consistency measure Consistency measure PMI values FMI values PVMI values k 13.12 13.3 13.07 R1 1.56 1.56 1.56 C1 0.01 0.025 0.006 C1/R1 \ 0.1 0.006 0.016 0.004 Fig. 3 Percentage weight for P.MI, F.MI and P.VMI graphically presented in Fig. 4. It can be observed that technologies T1, T3, T4, T6, T9 and T10 are essential for all MI groups, whereas technologies T5, T7, T8, T11 and T 12 are classified as supporting on the basis of threshold values defined above. In the end, technologies T2 and T13 are categorized as optional and can be dropped. 2.3 Comparing AHP and MWSM It is clear from Table 12 that the variance between criteria weight of AHP and MWSM of PMI is below 3%. However, as shown in Table 13, for FMI the variance is higher for C1, C5 and C6, which is between 6 and 7%. Similarly for P.MVI and as shown in Table 14, the variance of C1 and C6 is high in the vicinity of 6 and 7%. This indicates that technologies associated with C1 (text to speech), C5 (sensor and behavior) and C6 (text or digital mapping to speech) are affected by other technologies, and that explains why the AHP technique would have different weight for these criteria as it considers the correlation among different criteria. 3 Research paper assessment for MI A qualitative approach has also been proposed to determine the contribution of each technology for addressing the needs of the PwDs. These approaches have also been validated through their assessment of research papers addressing assistive technologies for people with motor impairment. To better understand the applications of the assessment techniques, explore their implications and identify their limitations, the review of selected research 20.0% 15.0% PMI 10.0% FMI 5.0% 0.0% PVMI T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 Table 9 Technologies classification Disabilities Essential List P.MI T1,T3,T4,T6, T9, T12 69.00% T2,T5,T10, T11 F.MI P.VMI T1,T3,T4,T6, T9,T10 T1,T3,T6,T7, T8,T9,T10, T12 76.00% 83.00% T5, T11 T11 Tech technologies, Per percentage 123 Tech Total per Supporting List Tech Total per Optional List Tech Total per 24.00% T7,T8,T13 7.00% 12.00% 5.00% T2, T7, T8, T12, T13 T2,T4,T5, T13 12.00% 12.00% Author's personal copy Univ Access Inf Soc (2018) 17:147–160 155 articles from the multiple academic disciplines that are related to different impairment conditions and most notably science, technology, and health is carried out [40]. The proposed quantitative and qualitative techniques have also been used to determine the areas where previous research was either limited or did not cover at all the needs of different groups of PwD. Table 10 Overall priority/weight for technologies Technologies Overall weight for MI (%) T1 14.5 T2 3.7 T3 10.3 T4 8.4 T5 4.0 T6 14.5 T7 4.5 T8 4.3 T9 10.3 T10 8.6 T11 6.2 T12 7.8 T13 3.0 Motor impairment (MI) is a physical disability that can be related to muscle weakness and fatigue, muscle contracture and spasticity. In the context of the present work, a total of 15 scientific papers that have tried to find solutions for disabled people with motor impairment are assessed. The review of selected research papers from multiple academic disciplines related to motor impairment conditions, most notably science, technology, and health is carried out by using the AHP assessment technique. The essential and important criteria that are relevant to the motor impairment group are shown in Tables 12 and 13 for P.MI and F.MI, respectively. These criteria are applied to the MI group, to better understand the application of the AHP assessment technique in evaluating these papers. Table 15 lists the average scores for the 15 papers assessed by those researchers related to MI according to the multi-weighted scoring method and the AHP model. As shown in Table 15, the average of the overall percentage covering the essential criteria for P.MI and F.MI was 62 and 57%, respectively. The number of papers covering the essential criteria with average C60% for P.MI is 7 out of 15 or 47%, and for F.MI is also 5 out of 15 or 33%. These results indicate that acceptable percentage of the papers for P.MI covered the essential criteria well for Table 11 Overall technologies classification P.MI, F.MI & P.VMI Essential List Tech Total percentage (%) Supporting List Tech Total percentage (%) Optional List Tech Total percentage (%) T1, T3, T4, T6,T9, T10 67.00 T5, T7, T8, T11, T12 26.00 T2, T13 7.00 Tech technologies Fig. 4 Importance for MI P.MI, F.MI and P.VMI 16.0% 14.0% 12.0% 10.0% 8.0% 6.0% 4.0% 2.0% 0.0% T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 123 Author's personal copy 156 Univ Access Inf Soc (2018) 17:147–160 Table 12 Criteria weight comparison between AHP and MWSM for P.MI C1 C2 C3 C4 C5 C6 MWSM 0.1 0.07 0.1 0.09 0.07 0.1 0.04 AHP 0.12 0.07 0.12 0.12 0.04 0.12 0.03 Variance (%) 2 0 2 3 -3 C7 2 C8 -1 C9 C10 C11 C12 0.04 0.1 0.1 0.1 0.1 0.02 0.12 0.07 0.07 0.12 C13 0.04 0.03 -2 2 -3 -3 2 -1 C8 C9 C10 C11 C12 C13 Table 13 Criteria weight comparison between AHP and MWSM for F.MI C1 C2 C3 C4 C5 C6 MWSM 0.11 0.02 0.11 0.11 0.11 0.1 0.03 0.03 0.11 0.08 0.11 0.04 AHP 0.17 0.02 0.11 0.11 0.05 0.17 0.02 0.02 0.11 0.11 0.07 0.03 Variance (%) 6 0 0 0 0 3 -6 C7 7 -1 -1 -4 -1 0.04 0.03 -1 Table 14 Criteria weight comparison between AHP and MWSM for P.VMI C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 C13 MWSM 0.09 0.06 0.09 0.06 0.06 0.09 0.09 0.09 0.09 0.09 0.09 0.09 0.09 AHP 0.15 0.03 0.09 0.03 0.03 0.15 0.09 0.09 0.09 0.09 0.05 0.09 0.15 Variance (%) 6 6 0 0 0 0 0 6 -3 0 -3 -3 -4 Table 15 Assessment table for P.MI and F.MI Criteria C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 C13 Total score for each paper (Percentage: per; coverage: cov; Essential: Ess) Weight (PMI) Weight (FMI) 0.12 0.07 0.12 0.12 0.04 0.12 0.03 0.02 0.12 0.07 0.07 0.12 0.03 0.17 0.02 0.11 0.11 0.05 0.17 0.02 0.02 0.11 0.11 0.07 0.03 0.03 Per of ess cov (C1 or C3 or C4, and C6, or C9, and C12) PMI (%) Per of ess cov (C1 or C3 or C4 and C6 or C9 or C10) FMI (%) MI-1 [20] 0.0 0.0 9.7 0.0 3.3 9.7 8.7 0.0 10.0 1.0 0.0 0.0 0.0 66 79 MI-2 [21] 10.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.5 0.0 0.0 0.0 0.0 45 61 MI-3 [22] 0.0 0.0 6.5 0.0 4.5 0.0 0.0 0.0 10.0 0.0 6.0 7.5 0.0 80 52 MI-4 [23] 9.0 0.0 0.0 8.5 0.0 0.0 0.0 0.0 8.0 0.0 0.0 5.5 0.0 75 70 MI-5 [24] 0.0 0.0 8.0 0.0 8.0 0.0 0.0 0.0 9.5 0.0 0.0 0.0 0.0 58 55 MI-6 [25] 0.0 0.0 7.5 0.0 2.0 9.0 0.0 0.0 10.0 0.0 0.0 0.0 0.0 58 69 MI-7 [26] 0.0 1.5 9.0 0.0 1.0 0.0 0.0 1.5 10.0 0.0 0.0 0.0 0.0 63 60 MI-8 [27] 0.0 1.5 8.5 0.0 1.5 0.0 0.0 1.5 10.0 0.0 0.0 0.0 0.0 62 58 MI-9 [28] 0.0 0.0 6.0 0.0 1.5 0.0 5.0 0.0 10.0 0.0 0.0 0.0 0.0 53 51 123 Author's personal copy Univ Access Inf Soc (2018) 17:147–160 157 Table 15 continued Criteria C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 C13 Total score for each paper (Percentage: per; coverage: cov; Essential: Ess) Weight (PMI) Weight (FMI) 0.12 0.07 0.12 0.12 0.04 0.12 0.03 0.02 0.12 0.07 0.07 0.12 0.03 0.17 0.02 0.11 0.11 0.05 0.17 0.02 0.02 0.11 0.11 0.07 0.03 0.03 Per of ess cov (C1 or C3 or C4, and C6, or C9, and C12) PMI (%) Per of ess cov (C1 or C3 or C4 and C6 or C9 or C10) FMI (%) MI-10 [29] 0.0 0.0 8.0 0.0 1.5 0.0 0.0 0.0 10.0 0.0 0.0 0.0 0.0 60 57 MI-11 [30] 2.0 10.0 8.0 0.0 0.0 0.0 0.0 0.0 9.5 0.0 0.0 10.0 0.0 92 55 MI-12 [31] 0.0 9.0 9.0 0.0 0.0 0.0 0.0 0.0 7.5 0.0 0.0 0.0 0.0 55 52 MI-13 [32] 0.0 0.0 9.5 0.0 0.0 0.0 0.0 0.0 2.0 0.0 0.0 0.0 0.0 38 36 MI-14 [33] 2.5 6.5 0.0 8.5 0.0 5.5 5.5 5.5 8.5 5.0 5.0 10.0 0.0 90 54 MI-15 [34] 0.0 0.0 9.0 0.0 4.0 0.0 0.0 0.0 6.0 0.0 0.0 0.0 0.0 50 47 63 57 Average percentage result: total score for each paper F.MI = 36%, and for P.MI = 26% Table 16 Assessment results of P.MI and F.MI Assessment parameters C1 (%) C3 (%) C4 (%) C6 (%) C9 (%) C10 (%) C12 (%) Percentage of coverage level of essential criteria relative to maximum value for P.MI by applying equation (5) of [17] 16 66 11 16 83 2 22 Percentage of coverage level of essential criteria relative to maximum value for F.MI value by applying equation (5) of [17] 16 66 11 16 83 4 Table 17 AHP weight—assessment table for P.VMI Assistive technology criteria for evaluation for the visual and motor impairment (VMI) group Percentage: Per; Essential: Ess; Coverage: Cov; Important: Imp; Criteria: Cri Criteria Criteria weight (P.VMI) C1 0.09 C2 0.06 C3 0.09 C4 0.06 C5 0.06 C6 0.09 C7 0.09 C8 0.09 C9 0.09 C10 0.09 C11 0.09 C12 0.09 C13 0.06 Per. of all Cri. of individual paper (%) Per. of Ess. Cov. (C1, C3, and C6 to C10 and C12) P.VMI (%) VMI-1 [35] 6.0 7.7 0.0 0.0 0.0 5.7 7.7 7.7 9.0 7.7 0.0 7.7 0.0 64 62 VMI-2 [36] 0.0 8.3 0.0 0.0 8.3 0.0 8.3 2.7 10.0 0.0 5.3 0.0 0.0 36 22 VMI-3 [37] 9.0 8.5 0.0 0.0 0.0 9.5 0.0 0.0 2.5 9.0 0.0 5.0 1.0 48 83 VMI-4 [38] 10.0 0.0 0.0 0.0 3.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 5.0 19 39 VMI-5 [39] 7.0 0.0 7.0 0.0 0.0 0.0 0.0 0.0 10.0 0.0 0.0 0.0 29 50 39 51 Average percentage of overall 5 papers 0.0 123 Author's personal copy 158 Univ Access Inf Soc (2018) 17:147–160 Table 18 AHP weight assessment results Relevant essential criteria for partial VMI C1 (%) C3 (%) C6 (%) C7 (%) C8 (%) C9 (%) C10 (%) C12 (%) Percentage of coverage level of essential criteria relative to maximum value for P.MVI. 64 14 30 32 21 63 33 25 the MI group, which would satisfy the needs of this group. However, 33% of these papers covered the essential criteria for F.MI. In terms of overall coverage of criteria, both P.MI and F.MI have a low score of 26 and 36%, respectively. Hence, further research is needed to cover multiple technologies with more comprehensive solutions to provide extra flexibility to MI users. The support of multiple technologies allows MI users to select the relevant technology to substitute their missing sensation caused by their motor impairment conditions. The technologies associated with relevant criteria for MI that require further investigation are analyzed and determined in the subsequent Sect. (3.1). address the needs of the P.VMI group through the support of multiple technologies associated with important criteria. The technologies associated with relevant criteria for P.VMI that need further investigation are analyzed and determined in the subsequent Sect. 4.1. 3.1 Assessing the coverage or relevant criteria in relation to the maximum value for MI The comparison of the coverage of each criterion in relation to other criteria is shown in Table 16 that illustrates the results after applying the essential criteria relative to the maximum value and by applying equation (5) of [17]. For partial MI, criteria C9 (display) and C3 (gesture control) are covered well among these 15 papers with average score of 83 and 66%, respectively, while other relevant criteria C1 (speech to text), C4 (tracking location), C6 (text to speech), C10 (voice control) and C12 (mobile support) have low score as shown in Table 16 and, therefore, are not covered well. This leads to the conclusion that further research in relation to C1, C4, C6, C10 and C12 is needed to improve the conditions for people with PMI. 4 Research paper assessment for P.VMI Table 17 lists the average scores of those researchers for the five papers related to P.VMI according to the MWSM. As shown, the average of overall percentage covering the essential criteria for P.VMI is 51%, while covering all criteria is 39%. These results indicate that none of these papers cover the essential criteria above 60% for P.VMI. Hence, further research is needed to cover multiple technologies for system input to provide extra flexibility to P.VMI users. Furthermore, more research needs to be carried out to reach a more comprehensive solution that can 123 4.1 Assessing the coverage of relevant criteria in relation to the maximum value for VMI Table 18 illustrates the average percentage of individual criteria results obtained by applying essential criteria relative to the maximum value and by applying equation (5) of [17]. For P.VMI, criteria C1 (speech to text) and C9 (display) are covered well among these five papers with values of 64 and 63%, respectively. This is followed up by C6 (text to speech), C7 (magnification) and C10 (adjustable speaker) with relatively acceptable scores of greater than 30%, while criteria C3 (gesture control), C8 (color control) and C12 (mobile support) have a lower score. This leads to the conclusion that further research in relation to C3, C8 and C12 should be conducted to improve the conditions for people with P.VMI. 5 Conclusion The assessment models applied in this article have not only successfully quantified the necessity of various technologies for each impairment group separately but also articulated the overall requirement of these technologies among different impairment groups. The assessment methodology of this article is primarily based on quantitative and qualitative assessment of various technologies in order to identify the applicability of the different proposed technological solutions in addressing the needs of the PwD. Two types of assessment models are applied in this study. The AHP scale is used to gather the assessment data for all thirteen technologies from experts, whereas MWSM is used to assess user rating. Afterward, MWSM rating would be converted to AHP scale for compatibility. The AHP model is implemented on the basis of relative importance of each technology depending on average scores of expert and user ratings. The significance of using the AHP model Author's personal copy Univ Access Inf Soc (2018) 17:147–160 is not only to give priority ratings for each technology with respect to disability but also to give overall scores to each technology for diversified disabilities. The AHP model assists in identifying more accurate weight of the criteria that are associated with these technologies since it considers the rating from experts and PwDs as well as determining the auto-correlation impacts among these criteria. It has also been observed that technologies T1, T3 (help in communication) can be ranked as the most essential in all kinds of physical impairment groups and technologies T3 (gesture control) and T9 (display system) can be ranked after these technologies. The criteria weights identified through the AHP model are then used to assess 15 scientific papers related to the different impairment groups related to MI and P.VMI of PwD by using the MWSM technique. The results of MI assessment indicate that some essential criteria are covered well in the literature as listed in Table 16, especially C3 (gesture control) and C9 (display), while other criteria associated with text to speech technologies (C1), tracking location (C4), speech to text (C6), speaker control (C10) and mobile support (C12) require further research in the literature, as their scores were low. The assessment result of P.VMI indicates that some essential criteria were covered well in the literature as listed in Table 18, especially C1 (text to speech) and C9 (display). In contrast, the rest of the criteria gesture control (C3), color control (C8) and mobile support (C12) which are relevant to P.VMI require further research, as their scores were relatively low. 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