Validity and Reliability of MOS Short Form Health Survey (SF-36) for Use in India.

BACKGROUND

Health is defined as the state of complete physical, mental and social well-being than just the absence of disease or infirmity. In order to measure health in the community, a reliable and validated instrument is required.

OBJECTIVES

To adapt and translate the Medical Outcomes Study Short-Form Health Survey (SF-36) for use in India, to study its validity and reliability and to explore its higher order factor structure.

MATERIALS AND METHODS

Face-to-face interviews were conducted in 184 adult subjects by two trained interviewers. Statistical analyses for establishing item-level validity, scale-level validity and reliability and tests of known group comparison were performed. The higher order factor structure was investigated using principal component analysis with varimax rotation.

RESULTS

The questionnaire was well understood by the respondents. Item-level validity was established using tests of item internal consistency, equality of item-scale correlations and item-discriminant validity. Tests of scale-level validity and reliability performed well as all the scales met the required internal consistency criteria. Tests of known group comparison discriminated well across groups differing in socio-demographic and clinical variables. The higher order factor structure was found to comprise of two factors, with factor loadings being similar to those observed in other Asian countries.

CONCLUSION

The item-and scale-level statistical analyses supported the validity and reliability of SF-36 for use in India.