This study in the first part has a cross-cultural adaptation design. The investigators
will use the CISS questionnaire modified by Ruijs, because the total score is between 0
and 100. For the PWES questionnaire the investigators will use the original version .For
translation and cross-cultural adaptation, no consensus exists. The investigators choose
the guidelines of AAOS outcomes committee which are widely used and accepted in the
literature.
The following five steps will be documented in a written report: (1) forward translation
from English to French by two translators whose native language is French and fluent in
English (T1 and T2). One of the translators is informed about the aims of the study and
the other received only limited information (so-called naive translator).Moreover, none
of the translators are physicians. (2) Synthesis of T1 and T2 will be done to form a
unique translated version T12 by resolving any discrepancies under supervision of a
methodologist not involved in the translation process. (3) Back translation of the T12
version from French to English by two English native speaking who are fluent in French
(BT1 and BT2). These two translators are naive to the study and not linked to the medical
domain. (4) Consensus meeting with all the involved subjects (translators, methodologist,
specialist physicians in rehabilitation) in order to resolve any discrepancies and doubts
met during the translation and to establish the pre final French version of the CISS and
PWES (5).
The investigators will verify content validity which is the ability to an instrument to
reflect the domain of interest and the conceptual definition of a construct i.e. cold
intolerance. For this purpose, the instructions, response format and the items of F-CIIS
and F-PWES questionnaire will be evaluated by a panel of 10 people for conceptual
equivalence (clarity). The expert panel will have knowledge's about the content areas of
the construct of the questionnaire and the target population of the questionnaire. The
mother language tongue of the expert panel is French. The experts have to rate if
instructions, response format and items are clear or unclear. If unclear they are asked
to provide suggestions for making the language clearer. If instructions, response format
and items are found to be unclear by at least 20 % of the panel, they have to be revised.
The minimum inter rater agreement among the experts panel is 80%.
Then the expert panel evaluate each item of the instrument for content equivalence, using
the following scale (1=not relevant, 2=somewhat relevant, 3=quite relevant, 4=highly
relevant). Items classified as 1 or 2 should be revised. Content validity index at the
item level (I-CVI) and at the scale level (S-CVI) should be calculated. The averaging
calculation of S-CVI (S-CVI/Ave) is the preferred method. With 10 experts, the I-CVI of
0.78 or above and an S-CVI/Ave of 0.90 or above are the minimum acceptable indices. Items
that do not achieve the minimum acceptable indices are revised and re-evaluated.
This part of the study which not concerned patients run from November 2019 to September
2020.
Pre final French version of the CISS and PWES will be administered to French native
speaking patients suffering from various hand injuries. 30 patients are sufficient[50].
They will be asked to write commentaries on difficulties of questionnaire's items,
especially comprehension of the different items (clear or unclear).If the item is
considered unclear, the patient is asked to provide suggestions for making the item
clearer .An item considered unclear by 20 % or more of the patients must be re-evaluated
. The definitive version of French-CISS and French PWES (F-CISS and F- PWES) and the
verification of the different stages of the cross-cultural adaptation will be validated
during a new consensus meeting.
For the second part (validation study) the investigators will administered F-CISS,
F-PWES, F-DASH, F-HFS, F-SF 36 questionnaires and a pain VAS to a population of 100 in
and outpatients with hand injuries. For F-CISS and F-PWES test-retest reliability, the
first 50 patients consecutively included will be asked to answer questionnaires 7 days
later .
The investigators propose to choose the cut-off of 30 points in the study to separate
which patient has a CI or not.
For the second part of the study, validation, different statistics will be made.
For internal consistency:
Exploratory factor analysis: 7 to 10 subjects per item are recommended with preference
for a sample ≥ 100 . To select the appropriate number of factors, many criteria might be
used. We can look at the screeplot, or take all components with an eigenvalue > 1 (Kaiser
Criterion). To interpret the factors, an orthogonal varimax rotation will be applied.
After that, items will be associated with a given factor if their loadings are higher
than 0.5 for the latter.
Calculation of Cronbach's α for the entire questionnaire and for the different
dimensions. A Cronbach's α ≥0.70 for the entire questionnaire and for the subscales is
required .
For test-retest reliability or reproducibility:
Intraclass Correlation Coefficient (ICC) are used. Since systematic difference is not
expected between test and retest, a two-way random effect model will be applied, so that
systematic difference are included in the measurement error. The investigators will study
50 patients with an interval of 7 days . The value of ICC should be >0.70 .
For construct validity: only the F-CISS will be studied. The F-PWES is only a scale for
screening people which are exposed to cold in their work and doesn't explore the same
dimensions. Pearson's correlation coefficient will be used.
Different hypotheses are posed.
The F-CIIS is well correlated with the F-DASH. A correlation ≥ 0.5 is expected.
The F-CISS is well correlated with the F-HFS. A correlation≥ 0.5 is expected.
The F-CISS is well correlated with pain VAS. A correlation ≥ 0.5 is expected. For
pain VAS the question will be: when you are exposed to cold how much is your pain?
We will use a 100 mm horizontal VAS.
The F-CISS is weakly correlated with SF36-PC. A correlation between 0.30 and 0.5 is
expected.
The F-CISS is not associated with SF36-MC. A correlation < 0.3 is expected. To have
a good construct validity, 75 % of the hypotheses should be satisfied .
Floor or ceiling effects: the distribution of scores will be observed and the
investigators expected no floor or ceiling effects (less than 15 % of respondents
achieved the highest or lowest possible scores).
