ARTHRITIS CARE & RESEARCH 45:167–173, 2001
ORIGINAL ARTICLE
An English and Spanish Quality of Life Measure
for Rheumatoid Arthritis
LEDA LAYO DANAO,1 GERALDINE V. PADILLA,2
AND
DOROTHY A. JOHNSON3
Objective. To develop a rheumatoid arthritis–specific health-related quality of life instrument, translate the English
instrument into Spanish, and test the scaling assumptions, reliability, validity, and feasibility of both the English and
Spanish versions.
Methods. The development of the Quality of Life–Rheumatoid Arthritis Scale (QOL-RA Scale) involved literature review,
consultations with experts, 40 face-to-face interviews, and 5 focus group discussions with multiethnic and multilingual
women with rheumatoid arthritis (RA). Translation design facilitated conceptual and linguistic equivalence. Data for the
psychometrics came from telephone interviews of a sample of 107 Caucasian/English and 80 Hispanic/Spanish women
with RA. The instruments were (a) the Arthritis Impact Measurement Scales 2 (AIMS2), (b) the Lubben Social Network
Scale (LSNS), (c) the Center for Epidemiologic Studies–Depression Scale (CES-D), and (d) the QOL-RA Scale. Descriptive
statistics, significance tests, Cronbach’s alpha technique, correlation, and factor analysis were used.
Results. The QOL-RA Scale, an 8-item scale, took 2 to 3 minutes to administer. Psychometric analysis revealed that the
psychometric attributes and constructs of both English and Spanish questionnaires are comparable (i.e., equivalent). Both
versions demonstrated the following: (a) normal distribution of the QOL-RA Scale, roughly symmetrical distributions of
the items, equivalent means and standard deviations across items, and less than 10% floor and ceiling effects, (b)
Cronbach’s alpha coefficients of 0.87– 0.90, (c) significant correlations of the QOL-RA Scale with the AIMS2 subscales,
LSNS, and CES-D, ranging from 0.25 to 0.66 (P < 0.01), and (d) extraction of 2 factors, namely physio-psychological and
socio-psychological, that explained 65% to 73% of the variance in the scale scores.
Conclusion. The QOL-RA Scale, in both English and Spanish versions, appears to meet the assumptions of a summated
rating scale and the criteria of relevance, reliability, validity, feasibility, and adaptability to several languages.
KEY WORDS. Health-related quality of life; Rheumatoid arthritis; Psychometrics; Multilingual.
INTRODUCTION
Interest in health-related quality of life (HRQOL) as an
important area of research is likely to increase with the
rising burden of chronic diseases, longer expectation of
Supported by NIH grants T32-NR-07072 (Institutional National Research Service Award: Quality of Life Research)
from the National Institute of Nursing Research and P60AR-36834 (Multipurpose Arthritis and Musculoskeletal Disease Center Grant, Subproject: Rheumatoid Arthritis and
Quality of Life) from the National Institute of Arthritis and
Musculoskeletal and Skin Diseases.
1
Leda Layo Danao, PhD, University of California School
of Nursing, Los Angeles, California, and University of the
Philippines Manila College of Nursing, Manila, Philippines;
2
Geraldine V. Padilla, PhD, University of California School
of Nursing, Los Angeles; 3Dorothy A. Johnson, DNSc, University of Southern California–Los Angeles County Medical
Center, Los Angeles, California.
Address correspondence to Leda Layo Danao, PhD, Postdoctoral Fellow, University of California School of Nursing,
P.O. Box 951702, Los Angeles, CA 90095-1702.
Submitted for publication May 31, 2000; accepted in revised form December 6, 2000.
© 2001, American College of Rheumatology
Published by Wiley-Liss, Inc.
life, the growing number of health intervention alternatives, and greater emphasis on humanizing health care
(1–3). In addition, decision-making on issues of cost-effectiveness across health inputs and resource allocation
across health programs is likely to be more sound if informed by HRQOL evidence (4 – 6). The continued significance and widespread use of HRQOL findings depend on
the quality of HRQOL theory and measurement.
Given that HRQOL is a multidimensional concept, the
question of just what its constitutive domains are remains
open. At the minimum, by the World Health Organization’s definition of health (7), these are the physical, emotional, and social well-being domains, as well as disease
activity (4,5,8 –10). A more expanded list is found in
Burckhardt et al. (11) and in Ventegodt (12). From the
conceptual and empirical work of the past 10 –15 years,
the most frequently cited elements to consider in the
choice of an HRQOL instrument are relevance, reliability,
validity, responsiveness, ease of application, and capability of adaptation into several languages (13–18).
In HRQOL assessments, there is an emerging consensus
that generic as well as disease-specific instruments should
167
168 Layo Danao et al
be used to measure the disease process and its overall
impact and to allow for comparisons across disease conditions and therapeutic outcomes (1,2,19 –22). A review of
the conceptual and measurement experience of HRQOL in
rheumatoid arthritis (RA) reveals a skewed emphasis on
physical function and a relative lack of attention given to
the psychological and social dimensions in the HRQOL
instruments currently in use for RA, a dearth of RA-specific HRQOL instruments, low relevance of existing instruments due to the omission of patient perspectives, scarcity
of studies conducted in natural clinical practice settings,
difficulties in instrument administration due to complexity, length, or need for trained interviewers (8,23,24), and
the absence of an RA-specific HRQOL instrument in Spanish.
RA is a chronic, progressive, and ultimately debilitating
health problem worldwide, to be so neglected. In the
United States, it is estimated that 1 percent of the adult
population or 2.1 million Americans aged 18 and older
have the disease (25). In Norway, the incidence of RA over
a 6-year study period was found to be 25.7 per 100,000
population (26), and in South Australia a representative
population survey found that 4 percent of the adult respondents reported having been told by their doctors that
they had RA (27).
The purpose of this study was to develop an RA-specific
instrument to measure the HRQOL of persons with this
disease in 2 ethnic/language groups, namely Caucasian/
English and Hispanic/Spanish. The objectives were to develop an RA-specific HRQOL instrument (QOL-RA) in English with procedures that enhance relevance and content
validity, to translate the English QOL-RA Scale into Spanish with procedures that enhance conceptual and linguistic equivalence, and to assess the scaling assumptions,
reliability, and validity of the English and Spanish versions of the QOL-RA Scale in 2 ethnic/language groups.
PATIENTS AND METHODS
Development of the Quality of Life–Rheumatoid Arthritis Scale. The development of the QOL-RA Scale was
guided by the conceptual definition of HRQOL as a personal statement of the positivity or negativity of the attributes that characterize life (28) and as a value imputed
by an individual to his or her life as modified by functional
states, impairments, and social opportunities influenced
by disease, injury, or treatment (29).
Development of the QOL-RA Scale involved 3 phases.
The first phase was the development of the English
QOL-RA Scale informed by an in-depth review and synthesis of existing concepts, measurements, and patient
experiences on the HRQOL of persons with RA, through an
extensive review of the literature; face-to-face interviews
of 40 Caucasian/English women about their experience
with RA and the HRQOL domains that were salient, relevant, and important to them; and a pretest of selected
instruments used in RA research with the same 40 women
as respondents. The second phase was the translation of
the English QOL-RA Scale into Spanish through forward
and backward translations of the English version to Span-
Vol. 45, No. 2, April 2001
ish by 2 bilingual research associates working independently; review of the Spanish translations to incorporate
Mexican, Central American, and South American linguistic idiosyncracies in the wordings of the questions in order
to produce a more generic Spanish version; and extensive
consultations with bilingual clinical and psychometric experts. In the third phase the Spanish version was examined more closely for salience, cultural relevance, clarity,
understandability, and format through a series of 5 focus
group discussions, with each group consisting of 4 –7 Hispanic/Spanish women with RA (30).
From the foregoing phases, 5 HRQOL domains were
identified and were included in the QOL-RA Scale,
namely physical function, social function, psychological
function, arthritis, and health. The physical function elements were physical ability and pain; the social function
elements were interaction with family and friends and
support from family and friends; and the psychological
function elements were tension and mood. Arthritis was a
disease-specific well-being element and health was a
global well-being element.
Subjects. The population for the study consisted of Caucasian/English and Hispanic/Spanish females, aged 18
and older, with RA in 5 health care facilities in the Los
Angeles metropolitan area. A consecutively accrued sample of 107 homebound Caucasian/English and 80 homebound Hispanic/Spanish females with RA participated in
the study. Recruitment was done in accordance with procedures approved by the human subjects review committee.
Instruments and variables. The instruments consisted
of the QOL-RA Scale, the Arthritis Impact Measurement
Scales 2 (AIMS2), the Lubben Social Network Scale
(LSNS), and the Center for Epidemiologic Studies–Depression Scale (CES-D).
The QOL-RA Scale is an RA-specific HRQOL instrument. It is an 8-item scale that measures the HRQOL of
persons with RA. Each item starts with the definition of an
element to be considered in rating one’s quality of life,
followed by a question on rating one’s quality of life on a
horizontal 10-point scale anchored with 1 (very poor) at
one end and 10 (excellent) at the other end. The elements
are physical ability, pain, interaction with family and
friends, support from family and friends, mood, tension,
arthritis, and health. The higher the QOL-RA Scale score,
the higher the HRQOL. A copy of the English and Spanish
versions of the QOL-RA Scale is given in the Appendix.
The AIMS2 subscales, LSNS, and CES-D were used as
criterion measures and were administered at the same time
as the QOL-RA Scale. These measures include the AIMS2
subscales of arm function, hand and finger function, walking and bending, mobility, household tasks, self-care,
pain, social support from family and friends, and tension;
LSNS interaction with family and friends; and CES-D depression. All scores ranged from 0 to 10. For the AIMS2
subscales and CES-D, the higher the score, the poorer the
respondent’s state on the measure, whereas for LSNS, the
Arthritis Care & Research
higher the score, the higher the level of interaction with
family and friends.
Data were collected by telephone interview in the language preferred by the respondent. The respondent followed along with copies of the questionnaires during the
interview, which lasted 20 to 30 minutes. The QOL-RA
Scale took 2 to 3 minutes to administer. Shortly after the
interview each respondent was sent a thank-you letter and
a check for $25.
Analysis. Scaling assumptions of the QOL-RA Scale
were examined with descriptive statistics (31). Chi-square
test, t-test, and Levene’s equality of variance test were used
to identify significant frequency, mean, and variance differences in sample characteristics, QOL-RA Scale scores,
and item scores. To determine reliability (internal consistency), Cronbach’s alpha and correlation coefficients were
generated. For criterion-related concurrent validity, the
QOL-RA Scale and items were correlated with the corresponding AIMS2 subscales, the LSNS, and the CES-D. For
construct validity, analysis of variance and factor analysis
were used (32). Level of significance was set at P ⱕ 0.01.
The similarity of the psychometric results across the
Caucasian/English and Hispanic/Spanish groups, in particular the similarity in constructs, will serve to illustrate
the capability of the QOL-RA Scale for adaptation to other
languages.
RESULTS
Sample characteristics. Chi-square tests showed no significant differences in functional class and RA severity
between the Caucasian/English and Hispanic/Spanish
groups. The Caucasian/English group was shown by t-test
to be significantly older, and chi-square tests showed the
same group to be significantly more likely to be married,
divorced, or widowed than single or separated, with
higher education and income, and more likely to be working or retired, compared with the Hispanic/Spanish group
(Table 1).
Scale characteristics. An examination of the scale characteristics in the Caucasian/English and Hispanic/Spanish
groups revealed normal distribution of the QOL-RA Scale
with a mean and standard deviation of 5.54 ⫾ 1.93 in the
Caucasian/English group and 5.28 ⫾ 1.73 in the Hispanic/
Spanish group. The distributions of the scale items were
non-Gaussian, although roughly symmetrical, except for
interaction with family and friends and support from family and friends, which were skewed to the right. Interaction with family and friends had the highest mean,
whereas arthritis and pain had the lowest means in, respectively, the Caucasian/English and Hispanic/Spanish
groups. In the Caucasian/English group, the means of 5
items fell between 5 and 6 on the 10-point scale; in the
Hispanic/Spanish group, the equivalent range was 4.99
and 6.08. The items with the top 3 means were interaction
with family and friends, support from family and friends,
and mood. The most heterogeneous items were support
English and Spanish HRQOL Measure for RA 169
Table 1. Demographic, socioeconomic, and disease
characteristics of the Caucasian/English and Hispanic/
Spanish groups
Caucasian/English Hispanic/Spanish
(n ⴝ 107)
(n ⴝ 80)
Mean age, years*
Age range, years
Marital status†
% single or separated
Education†
% ⬎12 years
Occupation†
% full-time or retired
Income†
% ⬎$30,000/year
Functional class
% class I
% class II
% class III
% class IV
Severity
% mild
% moderate
% severe
51.96 ⫾ 14.50
22–81
45.43 ⫾ 13.92
20–78
25.23
46.25
56.07
13.75
29.91
1.25
28.97
1.25
9.34
48.60
36.45
5.61
7.50
46.25
42.50
3.75
25.23
50.47
24.30
12.50
57.50
30.00
* t-test differences between the Caucasian/English and Hispanic/
Spanish groups significant at P ⱕ 0.01.
† Chi-square test differences between the Caucasian/English and
Hispanic/Spanish groups significant at P ⱕ 0.01.
from family and friends, interaction with family and
friends, and pain in the Caucasian/English group, and the
equivalent in the Hispanic/Spanish group were pain, support from family and friends, and health. With one to two
exceptions, all points on the scale of each item were used
(Table 2).
The performance of t-tests for equality of means and
Levene’s test for equality of variances between the Caucasian/English and Hispanic/Spanish groups showed no significant difference across the QOL-RA Scale and the 8
items.
Floor and ceiling effects. As shown in Table 2, the
QOL-RA Scale had negligible floor and ceiling effects in
both ethnic/language groups. In the Caucasian/English
group, floor and ceiling effects were well below 10 percent,
except for interaction with family and friends (ceiling) and
support from family and friends (ceiling). Similarly, no
higher than 10 percent floor and ceiling effects were found
in the Hispanic/Spanish group, with the exception of pain
(floor), interaction with family and friends (ceiling), support from family and friends (ceiling), and health (ceiling).
Inter-item correlations. In the Caucasian/English
group, 26 of the 28 item correlations were within the
0.30 – 0.70 range (Table 3). The correlations of arthritis
with physical ability (0.72) and health (0.75) were higher
than the upper limit of the range. In the Hispanic/Spanish
group, all correlations except 2 were within the 0.30 – 0.70
range. The exceptions were the correlations between
health and tension (0.23) and between arthritis and support from family and friends (0.28). Item homogeneity (28)
170 Layo Danao et al
Vol. 45, No. 2, April 2001
Table 2. Quality of Life–Rheumatoid Arthritis Scale (QOL-RA Scale): means, standard deviations (SD), and percent floor and
ceiling scores in the Caucasian/English and Hispanic/Spanish groups
Caucasian/English (n ⴝ 107)
Hispanic/Spanish (n ⴝ 80)
Scale items
Mean ⴞ SD
% floor
% ceiling
Mean ⴞ SD
% floor
% ceiling
Physical ability
Pain
Interaction
Support
Mood
Tension
Arthritis
Health
QOL-RA Scale
5.76 ⫾ 1.98
5.46 ⫾ 2.31
7.21 ⫾ 2.32
6.95 ⫾ 2.43
6.22 ⫾ 2.19
5.74 ⫾ 2.22
5.28 ⫾ 2.28
5.60 ⫾ 2.17
5.54 ⫾ 1.93
2.8
5.6
1.9
1.9
5.6
2.8
7.5
3.7
0.9
2.8
2.8
18.7
20.6
5.6
4.7
1.9
2.8
0.9
5.29 ⫾ 1.88
4.76 ⫾ 2.39
6.94 ⫾ 2.21
6.49 ⫾ 2.31
6.08 ⫾ 2.14
5.65 ⫾ 2.03
4.99 ⫾ 2.04
5.84 ⫾ 2.26
5.28 ⫾ 1.73
5.0
15.0
0.0
1.3
1.3
5.0
10.0
3.8
2.5
1.3
2.5
17.5
15.0
7.5
3.8
1.3
11.3
1.3
was 0.53 and 0.45 in the Caucasian/English and Hispanic/
Spanish groups, respectively.
Reliability. Cronbach’s alpha coefficients of the
QOL-RA Scale in the Caucasian/English and Hispanic/
Spanish groups were 0.90 and 0.87, respectively. The alpha coefficients, if the item was deleted, ranged from 0.89
to 0.91 in the Caucasian/English group and from 0.84 to
0.86 in the Hispanic/Spanish group. The item-to-total correlations, corrected for overlap, ranged from 0.52 to 0.77 in
the Caucasian/English group and from 0.55 to 0.75 in the
Hispanic/Spanish group.
Criterion-related concurrent validity. The QOL-RA
Scale correlated significantly with the AIMS2, LSNS, and
CES-D measures. In the Caucasian/English group, all coefficients except 2 (those with AIMS2 self-care and LSNS
interaction with family and friends) were significant, ranging from ⫺0.30 to ⫺0.60. In the Hispanic/Spanish group,
all coefficients except 1 (that with AIMS2 mobility) were
significant, ranging from ⫺0.30 to ⫺0.52.
In both ethnic/language groups, the correlation of the
scale items with the criterion measures revealed that the
highest coefficients were between the QOL-RA Scale item
and its corresponding criterion measure or measures, for
example QOL-RA physical ability with AIMS2 physical
activity subscales, QOL-RA pain with AIMS2 pain, and so
on. The only exception was the QOL-RA interaction with
family and friends and the LSNS interaction with family
and friends coefficient, which was lower than the coeffi-
Table 3. Quality of Life–Rheumatoid Arthritis Scale (QOL-RA Scale): inter-item correlations in the Caucasian/English and
Hispanic/Spanish groups
Caucasian/English (n ⴝ 107): r coefficients
Scale items
Physical
ability
Pain
Interaction
Support
Mood
Tension
Arthritis
Physical ability
Pain
Interaction
Support
Mood
Tension
Arthritis
Health
0.63
0.37
0.31
0.52
0.54
0.72
0.54
0.35
0.42
0.58
0.54
0.70
0.68
0.62
0.67
0.51
0.47
0.52
0.43
0.38
0.37
0.38
0.60
0.61
0.59
0.55
0.62
0.75
Health
Hispanic/Spanish (n ⴝ 80): r coefficients
Scale items
Physical ability
Pain
Interaction
Support
Mood
Tension
Arthritis
Health
Physical
ability
Pain
Interaction
Support
Mood
Tension
Arthritis
0.66
0.50
0.48
0.60
0.54
0.58
0.46
0.33
0.35
0.49
0.36
0.57
0.39
0.48
0.54
0.49
0.31
0.40
0.33
0.42
0.28
0.44
0.52
0.53
0.36
0.36
0.23
0.64
Health
Arthritis Care & Research
English and Spanish HRQOL Measure for RA 171
Table 4. Quality of Life–Rheumatoid Arthritis Scale (QOL-RA Scale): factor structure, loadings, and percent of variance
explained in the Caucasian/English and Hispanic/Spanish groups
Caucasian/English (n ⴝ 107)
Scale items
Arthritis
Physical ability
Pain
Health
Tension
Mood
Interaction
Support
% variance explained
Factor I
0.86
0.85
0.83
0.78
0.67
0.58
60.66
Hispanic/Spanish (n ⴝ 80)
Factor II
0.58
0.86
0.85
12.64
cient of the same QOL-RA item and CES-D depression, in
the Caucasian/English group. The QOL-RA physical ability and AIMS2 pain coefficient was equivalent to the
QOL-RA physical ability and the AIMS2 physical activity
coefficients.
In the Caucasian/English group, the QOL-RA arthritis
and QOL-RA health items correlated significantly with 7 to
8 of the 11 criterion measures. In contrast, in the Hispanic/
Spanish group, the QOL-RA arthritis and QOL-RA health
items correlated significantly only with the AIMS2 pain
and AIMS2 support from family and friends, respectively.
Construct validity. The HRQOL of persons with RA is
expected to vary indirectly with severity of illness. Using
3 RA severity subgroups of mild (Caucasian/English, n ⫽
27; Hispanic/Spanish, n ⫽ 10), moderate (Caucasian/English, n ⫽ 54; Hispanic/Spanish, n ⫽ 46), and severe
(Caucasian/English, n ⫽ 26; Hispanic/Spanish, n ⫽ 24),
the analysis of variance test was used to compare the
QOL-RA Scale and item scores across the 3 severity subgroups.
In both ethnic/language groups, the QOL-RA Scale
means were significantly different across the severity subgroups. In the Caucasian/English group, the severity subgroups were significantly different in the scale items of
physical ability, pain, mood, arthritis, and health. In the
Hispanic/Spanish group, the differences in the scale items
of arthritis and health were significant across severity subgroups.
Factor analysis was done to analyze the factor structure
and factor loadings of the QOL-RA Scale. The methods of
principal components analysis and varimax orthogonal
rotation were used. The results are shown in Table 4.
In both ethnic/language groups, 2 factors were extracted.
Factor I was labeled “physico-psychological factor,” and
factor II was labeled “socio-psychological factor.” Instead
of constituting a separate factor, the psychological function items of tension and mood loaded substantially on
both the physical and social function factors.
In the Caucasian/English group, the scale items arthritis,
physical ability, pain, health, tension, and mood loaded
substantially on factor I, which explained 60.66 percent of
the variance in the scale scores, and the items of interaction with family and friends, support from family and
Scale items
Arthritis
Pain
Health
Physical ability
Mood
Tension
Interaction
Support
% variance explained
Factor I
0.90
0.75
0.71
0.67
0.55
52.44
Factor II
0.50
0.52
0.70
0.84
0.78
12.96
friends, and mood loaded substantially on factor II, which
explained 12.64 percent of the variance in the scale scores,
for a total of 73.30 percent variance explained in the scale
scores by the 2 factors.
In the Hispanic/Spanish group, except for the scale item
tension, the same items as in the Caucasian/English group
loaded substantially on factor I, which explained 52.44
percent of the variance in the scale scores. As in the
Caucasian/English group, the items interaction with family and friends, support from family and friends, and mood
loaded substantially on factor II; in contrast to the Caucasian/English group, the items tension and physical ability
loaded substantially on factor II as well, which explained
12.96 percent of the variance in the scale scores, for a total
of 65.40 percent variance explained in the scale scores by
the 2 factors.
DISCUSSION
It appears that the QOL-RA Scale, by its scale and item
characteristics and inter-item correlations, meets the assumptions of a summated rating scale. Its low floor and
ceiling effects allow for both deterioration and improvement of the respondent’s condition within the scale. The
scale had moderately high to high internal consistency,
and the substantial item-to-total correlations, corrected for
overlap, were indicative of a significant contribution of
each item to the total score. Significant scale and item
correlations with AIMS2 subscales, LSNS, and CES-D, criterion measures that were administered simultaneously
with the QOL-RA scale, suggested criterion-related concurrent validity. By discriminating across RA severity subgroups, construct validity was supported. The 2-factor factor structure, which showed that the psychological
function loaded substantially on both physical function
and social function, supported construct validity as well.
Because the results on scale characteristics, floor and
ceiling effects, inter-item correlations, internal consistency, criterion-related concurrent validity, and construct
validity were equivalent across the Caucasian/English and
Hispanic/Spanish groups, it appears that the English and
Spanish versions of the QOL-RA Scale have satisfactory
psychometric properties.
172 Layo Danao et al
The development of the scale reflected patient, expert,
and literature perspectives, thus enhancing scale relevance and content validity. The rigorous translation procedures were helpful in achieving conceptual and linguistic equivalence between the English and Spanish versions
and enhanced the appropriateness of the Spanish version.
The scale is simple, short, and easy to administer by self or
via telephone and is therefore ideal for routine use in a
busy clinical practice setting. Respondent burden is reduced to a minimum, thus encouraging higher participation and completion rates. The scale appears to be the
second RA-specific HRQOL English multidimensional instrument reported in the literature (24), and, as far as we
know, it is the first of its kind in Spanish, which makes the
scale likely to be useful in multiethnic and multilingual
practice and research settings.
The scale and its items need further study. For example,
the social function items of interaction with family and
friends and support from family and friends were highly
skewed to the right, with the highest means, standard
deviations, and ceiling effects, and these therefore need
further attention. Although significant correlations were
found between the QOL-RA Scale and the AIMS2 subscales, LSNS, and CES-D, the magnitudes of these coefficients were not as high as the 0.75 standard set in Kline
(33) for criterion-related validity. The reasons could be
methodological or conceptual and need to be explored
further. Another finding that deserves closer scrutiny is
factor II of the factor analysis in the Hispanic/Spanish
group, which showed substantial loadings of all 3 HRQOL
dimensions of social, psychological, and physical functions— one of its few differences with the Caucasian/English group, whose factor II was a more clear-cut sociopsychological factor.
Another concern is that the participants in this study
were limited to women with RA, and the scale should be
tested among men with RA in order to enhance sex generalizability. In addition, testing in other research and clinical settings is necessary. Scale responsiveness, relationship with clinical and other disease activity measures, and
test–retest reliability are important psychometric properties that should be studied in the future.
It would have been ideal to compare the QOL-RA Scale
with the RAQoL, the first English RA-specific quality of
life instrument. The latter is a 30-item questionnaire, with
a Yes/No response format that was reported to be valid,
reliable, simple to administer, and adaptable to several
languages (24). Although practical considerations prevented such a comparison here, doing so in the future
would be useful in addressing construct, method, and
psychometric comparability issues.
Finally, the scale assumes that respondents are discerning of the health-related quality of their lives and are able
to make the correspondence between their assessments
and the numerical values on the scale. A second assumption is that respondents are able to distinguish between the
various dimensions of and evaluate the respective importance of each of these on their HRQOL. Future research on
the QOL-RA Scale will reveal the validity of these assumptions.
Vol. 45, No. 2, April 2001
ACKNOWLEDGMENTS
We wish to acknowledge the contributions of K. Hayashi,
E. Berkanovic, B. Ferrell, J. Louie, E. Schladweiler, G. van
Servellen, and A. Wong. We also wish to thank Lynn
Brecht for her statistical advice.
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APPENDIX
Quality of Life–Rheumatoid Arthritis Scale (QOLRA Scale): English and Spanish versions
English version
1. Considering your physical ability, how would you rate
your quality of life?
Very poor 1 2 3 4 5 6 7 8 9 10 Excellent
2. Considering the help that you receive from family and
English and Spanish HRQOL Measure for RA 173
3.
4.
5.
6.
7.
8.
friends, how would you rate your quality of life?
Very poor 1 2 3 4 5 6 7 8 9 10 Excellent
Considering your arthritis pain, how would you rate
your quality of life?
Very poor 1 2 3 4 5 6 7 8 9 10 Excellent
Considering your level of tension, how would you rate
your quality of life?
Very poor 1 2 3 4 5 6 7 8 9 10 Excellent
Considering only your health, how would you rate your
quality of life?
Very poor 1 2 3 4 5 6 7 8 9 10 Excellent
Considering only your arthritis, how would you rate
your quality of life?
Very poor 1 2 3 4 5 6 7 8 9 10 Excellent
Considering your level of interaction with your family
and friends, how would you rate your quality of life?
Very poor 1 2 3 4 5 6 7 8 9 10 Excellent
Considering your mood, how would you rate your quality of life?
Very poor 1 2 3 4 5 6 7 8 9 10 Excellent
Spanish version
1. Si Ud. considera sólo sus habilidades fı́sicas, ¿dirı́a que
su “CALIDAD DE VIDA” es?:
Muy mala 1 2 3 4 5 6 7 8 9 10 Excelente
2. Si Ud. sólo considera la ayuda que le han dado su
familia y sus amistades, ¿dirı́a que su “CALIDAD DE
VIDA” es?:
Muy mala 1 2 3 4 5 6 7 8 9 10 Excelente
3. Si Ud. sólo considera su dolor artrı́tico, ¿dirı́a que su
“CALIDAD DE VIDA” es?:
Muy mala 1 2 3 4 5 6 7 8 9 10 Excelente
4. Si Ud. sólo considera su nivel de tensión nerviosa,
¿dirı́a que su “CALIDAD DE VIDA” es?:
Muy mala 1 2 3 4 5 6 7 8 9 10 Excelente
5. Si Ud. sólo considera su salud, ¿dirı́a que su “CALIDAD
DE VIDA” es?:
Muy mala 1 2 3 4 5 6 7 8 9 10 Excelente
6. Si Ud. sólo considera su artritis, ¿dirı́a que su “CALIDAD DE VIDA” es?:
Muy mala 1 2 3 4 5 6 7 8 9 10 Excelente
7. Si Ud. sólo considera su nivel de interacción entre Ud.
y su familia y amigo(a)s, ¿dirı́a que su “CALIDAD DE
VIDA” es?:
Muy mala 1 2 3 4 5 6 7 8 9 10 Excelente
8. Si Ud. sólo considera lo que Ud. dijo acerca de su
estado de ánimo, ¿dirı́a que su “CALIDAD DE VIDA”
es?:
Muy mala 1 2 3 4 5 6 7 8 9 10 Excelente