Persian adaptation of a questionnaire of environmental risk factors in multiple sclerosis (EnvIMS-Q)

Background: It seems that gene-environment interaction play most important role in Multiple Sclerosis development. Increasing the incidence and prevalence of MS during the recent decades in the low prevalence area such as Iran is explained better by environment factors. Environmental Risk Factors in Multiple Sclerosis (the 'EnvIMS-Q') is a 6-page self-administered questionnaire for case control studies.

Objectives: the objectives of study are validation and adaptation of the EnvIMS-Q' then development of a Persian version for case control studies in Persian population.

Methods: This questionnaire translated literally and in culturally relevant form, then content validation process was done by three groups' experts. According to giving rating to each item, each section and the whole instrument, we calculated their content validation indexes and also added some new questions and a new section to EnvIMS-Q. Finally, we analyzed repeatability of the answers within a 4 weeks interval.

Results: Relevancy and clarity indexes of all items were more than 80%. Scale relevancy index equaled 99% and scale clarity index equaled 97%. Repeatability of most items was acceptable.

Conclusions: the use of standardized validated questionnaires will assist the researchers to perform local studies on the role of environmental factors on the basis of reliable data.