
Background: KOOS is a self -administered instrument which assesses patient's opinion about Knee associated problems. Original version of KOOS has been translated in various regional foreign languages. India, is multilingual country where each province has a unique language. Maharashtra is the second largest state in India and Marathi is the regional language of the communication. KOOS is a self‐report disease specific measure needed to be translated with unique method in order to achieve a normative equivalence and linguistic validation. Methods: After obtaining permission from KOOS web manager T1, T2, T12, B1 & B2 versions were formatted according to the guidelines laid down by AAOS for cross cultural adaptation of health status measure. T12 version was sent for the field testing. Total 32 subjects were included in this trial. Results: Statistical analysis for reliability with test re‐test method suggested perfect correlation (r =1) between day 1 & 2. A range of 0.83‐0.54 co‐relation co‐efficient (r) demonstrated validity of KOOS and its subscales when compared against the 8 different domains of SF‐36. All this correlations were statistically highly significant. Sport and recreation subscale had many missing responses since many items in this subscale were not appropriate for the Maharashtrian cultural set-up. Participants provided information about other functional activities which were specific to Indian cultural set up and difficult to execute due to knee associated impairments. Conclusion: Marathi version of KOOS proved to be a reliable & valid measure.