Hamilton Regional Laboratory Medicine Program
A Collaborative Program of the Hamilton Health Sciences,
St. Joseph's Healthcare and McMaster University
SI Manual in Health Care - Second Edition
C.2 Guidelines for Administrators and Department Heads in Implementing SI*
*Note: Most of the information in Section C.2 is taken from the World Health Organization Chronicle. 32:92-98 (1970)
There are three main elements in the successful transition to SI units: setting a target date, planning and instruction. It is
strongly recommended that a co-ordinating committee be established within the health care institution to co-ordinate the
conversion to SI within the various departments. This co-ordinating committee can obtain further guidance from the
various provincial health co-ordinators (see Appendix VII).
Since the change to SI units affects laboratories to a far greater extent than other departments, much of the
responsibilities for planning will fall on the laboratory. The SI Manual in Health Care provides technical data and
conversion tables to help the laboratory in this endeavour.
Setting the Target Date
Early in conversion preparations, a target date for the change should be set. Experience in countries that have already
made the change demonstrates that beyond any doubt, this period should be as short as possible. On the basis of this
experience, it is strongly recommended that an actual date be set rather than a period-for example, "the change will take
place at midnight on 15 November 1981," not "the change will take place during November 1981."
Planning in the Institution
Each institution should make careful plans for the implementation of the change, including a program of instruction.
Arrangements should be made to secure "outside" speakers, if possible, for some of the instructions. charts of
equivalent scales in old and SI units for the most important tests (and, at the appropriate time, displayed in prominent
positions) and small (pocket-size) cards with similar scales should be made available for distribution to all personnel.
(See Appendix X for reference material). It is suggested that such pocketsize cards be prominently displayed near the
telephone in each ward or clinic where telephoned results are received from the laboratory. All laboratory report forms
should be reviewed to determine if any of them need to be revised. If so, arrangements for the printing of new ones
should be made. (In some hospitals, all report forms have been redesigned, each bearing a printed reminder of the fact
that SI units are being used. Others have avoided this expense by using a rubber stamp as a reminder.) The clinical
chemistry department should check to see what, if any, modifications, will be necessary to automated analysis
equipment, and arrange to have such modifications made at the appropriate time. (In practice it has been found that, in
most cases, such modifications are a simple matter).
Instruction on SI
The in-service education department of various institutions will greatly influence the promotion and acceptance of the
use of SI. For the program to be beneficial and successful, persons teaching the subject should be knowledgeable and
comfortable with the usage of SI units. A person from the in-service education department should be on the metric
committee of the institution.
entitled SI UNITS: How make the change.
See Appendices Vlll and IX for an outline of activities to consider in SI conversion.
A general awareness program should be given to all staff presently employed in the institution to familiarize them with
the most commonly used units, and to inform them of the implementation dates. New staff should also receive this
information during their orientation.
C.2 Guidelines for Administrators and Department Heads in Implementing SI* Cont.
There should be a period of not more than six months for this instruction. Most of the six-month period will cover general
instruction on the structure of SI and the reasons for adopting it. Detailed instruction should be left to the end. During the
last month of this period, a short and intensive program of instruction should be devised to explain conversion
procedures, allowing plenty of opportunity for detailed discussion of problems that might arise.
The instruction should cover the following topics:
1. A brief discussion on how SI came into being, who developed it, and why it is necessary. Here it is important to
emphasize that SI is not just a change for the sake of change, but that it is essential as a universal language of
measurement. (Care should be taken, however, not to imply that instant utopia will result on the day when the
change is completed).
2. A thorough description of SI and of the way it is constructed emphasizing the simplicity of the system, i.e. no
mathematical factors other than 1 are involved in the formation of derived units (The slide-tape program on SI,
prepared by Dr M.J. McQueen is recommended for training. See Other Reference Material - Clinical
Laboratories Section).
3. A detailed discussion of the practical application of SI to the health professions. A large part of this phase of
instruction should deal with the use of the mole and its advantages (in comparison with the traditional mass
units) and should be fully, clearly, and simply explained. It should be emphasized that the mole is not merely a
new unit whose use entails only a conversion factor (as was the case, for example, in the change from grains to
milligrams), but that it involves a conceptual change in dimensions from mass to active particles.
4. Detailed information on the way the change is to be implemented in the institution. The lists of new units and
reference values should be distributed at this time, together with sample copies of any new laboratory report
forms that have been prepared.
In phases one and two of the instruction period, it is desirable that experts from outside the institution take part in the
discussion wherever possible. In this area, "the best available advice and information," to use the words of the World
Health Assembly, is often not to be found in the institution, or even in the health professions. For example, in teaching
hospitals attached to universities, it is highly desirable that members of the faculties of natural sciences take part in
these phases of instruction, since they can often provide the best available advice and information on what SI is. Such
joint sessions will, furthermore, emphasize the universality of SI and the fact that the new system is a common language
for the entire scientific community.
Phase three of the instruction will be given largely by members of the institution's own staff, although even here it will
often be possible for outside specialists or consultants (clinical chemists, biochemists, physiologists, etc.) to take part.
Phase four is entirely the responsibility of the institution itself.
Through the entire period of instruction, it is essential that each talk, lecture or discussion be followed by a questionand-answer period.
Those who are not affiliated with any institution, e.g. physicians in private practice and pharmacists who operate their
own business establishments, are clearly in a less favoured position than institutional personnel. To a large extent, they
must rely on information published in their professional journals and on literature distributed by the ministry/ department
of health, or by professional associations. In many cases, however, it will be possible for local professional associations
to arrange conferences or seminars, at which instruction can be given and questions answered. It is strongly
recommended that this be done wherever possible.
Implementation
If the steps suggested above are followed, the day of change should present few if any difficulties. However, careful
attention to detail is essential. In particular, the necessity of writing careful, legible, unambiguous reports should be
impressed on all laboratory personnel. Such personnel should be instructed to exercise special care in making
telephone reports of laboratory tests. Only in emergency cases should telephone reports be made, and the technician
making the report must make sure that the numerical value and the unit are clearly understood. All telephone reports
should be followed immediately by a confirmatory report in writing.
For the first few days, everyone will need constant reminders that units (and most numerical values) have changed.
Reports can be marked (by means of a rubber stamp) with the letters "SI" in red, and attention should be drawn to
unusual results. Mistakes that occur during this phase are invariably due to someone forgetting that the units have
changed.
Finally, a factor of major importance. Clinicians who use laboratory reports will naturally be concerned about the
dangers of misinterpreting values in new units. They may feel that an interim period should be adopted to permit
reporting in both SI units and old units. However, experience has shown, without exception, that nothing is gained from
this practice; on the contrary, it leads only to confusion and may well result in failure to achieve a successful transition. It
is therefore strongly recommended that no interim period be used to allow laboratory reports to be made in both SI units
and old units. The date of change should be just that- a date of change to the international system. If the planning and
instruction have been carried out carefully, the change will be trouble-free.
C.2 Guidelines for Administrators and Department Heads in Implementing SI* Cont.
Suggested Timetable
D* Minus 12 months Target data set. A list of SI units and reference values are printed.
D
Minus 9 months
Each institution begins planning for instruction and implementation.
D
Minus 6 months
Each institution begins general instruction of its personnel.
D
Minus 1 month
Each institution begins intensive instruction.
D refers to the date of the change to the SI system.