An observational study was conducted in two phases namely the translation phase and the validation phase. Each phase was carefully conducted so as to eliminate bias and to produce reliable results. Ethics approval was obtained from Medilink Ethics Committee, Ahmedabad. Before starting the translation work of LEFS, a written approval from the original author Binkley JM was obtained. The copyright holder of the original LEFS authorised the study and publication of the work. The study period was 3 months, from July 2017 to September 2017.

The LEFS is a 20-item questionnaire designed to be applicable to individuals with musculoskeletal conditions of the lower extremity. Each item of the LEFS scores on a 5-point scale ranging from 0 to 4 points. When scoring the LEFS, up to four missing item responses are permitted. LEFS scores range from 0 to 80 points, with higher scores representing higher levels of functioning [6].

Procedure: Translation of the LEFS from its original English version to the Gujarati version was performed following the forward/backward translation guidelines [23]. This method was performed to ensure the translated version is grammatically sound and the terms used are correct. At the same time the meaning and contents of original LEFS are well preserved.

First, translation into Gujarati was performed independently by two Gujarati native speakers, one familiar with healthcare and its terminology and the other not familiar with healthcare and its terminology (T1 and T2, respectively). Subsequently, a version combining both initial translations (T1/T2) was written, based on consensus of the two initial translators. Some adaptations of the original questionnaire were defined during the translation process to suit the Gujarati culture and traditions. This synthesised version was then back-translated into English by two independent professional translators (BT1 and BT2) to allow verification of consistencies with the original English version.

These versions (BT1 and BT2) were then sent for a comparative analysis with the original version to experts of the committee composed of orthopedic surgeons, physical therapists, and researchers for the dissemination in Guajarati [Table/Fig-1]. Each item was analysed as accepted, accepted with modification or rejected. Their reviews and feedback were considered and modifications were done accordingly.

This pre-final version was presented in a group of 10 patients [Table/Fig-2] with a variety of lower limb conditions to explore the clarity of the questionnaire. Sample size was set as 10 for the initial target number of respondents for validation of the 20-item LEFS and the participants were selected by the simple random sampling method. The participants were selected from those visiting the Physiotherapy department of Ahmedabad. The inclusion criteria for the respondents were males or females in the age group from 25-85 years with ability to read and understand Gujarati and an examination suggestive of lower limb affection. The exclusion criteria were any systematic disease or neurologic condition other than musculoskeletal pathologies. Participants who were eligible for this study were informed about the purpose of the study and the methodology. Written informed consent was obtained and questionnaire was handed to them to fill up. All patients were asked whether they understood the items and whether they could interpret the questionnaires correctly.

The scores were calculated for each participant and recorded. The participants were ensured of the confidentiality of the study. This procedure was repeated after a week again with the same participants and scores were recorded (To know the test-retest reliability of the LEFS). The completed questionnaires were evaluated to determine the presence of missing responses and language difficulties. There was no specific difficulty in translated LEFS. Thus, this version was accepted for use in a larger patient population.

The findings were discussed among the translators, resulting in only minor changes to the final Gujarati version of the LEFS. The final version of the LEFS in Gujarati was then approved by the expert committee and validated using appropriate statistical analysis. Test- retest reliability and internal consistency were assessed using SPSS version 20.

The mean age of the participants was 50.2 years including 7 males and 3 females. All 20 items listed in the LEFS questionnaire were validated to measure lower limb function in various aspects.

Reliability concerns the degree to which the results of measurement are consistent across repeated measurements. Test-retest reliability of the Gujarati LEFS was determined by means of Intraclass Correlation Coefficients (ICC) at 95% confidence intervals and internal consistency, an indicator for the homogeneity of a questionnaire was assessed with Cronbach’s alpha. The Gujarati version of the LEFS had high internal consistency and test-retest reliability with Cronbach’s α=0.809 and intraclass correlation coefficient=0.809 (95% CI: 0.58, 0.94). The reliability was high for inter-interviewer measures too with an ICC of 0.98 (95% CI: 0.95, 0.99) [Table/Fig-3].

The study was conducted as there was a need for an instrument to measure health related quality of life, especially concerning lower limb in Gujarati population. Being a self-report questionnaire, LEFS provides us an important applicability in both clinical and educational settings. Therefore, it is important to employ a validated health related outcome measures. Adaptation may be required to ensure it is both culturally and linguistically appropriate.

The primary objective of this study was to create a reliable and valid Gujarati version of LEFS by translation and adaptation. No difficulties were encountered in the translation phase of the study; the structure of the original LEFS was not altered and all items were maintained.

Total 7 items (Questions 3, 5, 10, 11, 12, 15, and 19) were modified as per suggestions given by experts and considering the Gujarati population. None of the items were rejected. No change was made in sequence of item presentation. Also the items were numbered in Gujarati, However, in the Brazil version [3] of the LEFS the items were sequenced alphabetically instead of numbers as in Original LEFS.

The item 3 of original LEFS “Getting into or out of the bath” was modified to “while taking bath”. Bathing was considered as an activity of daily living which was important to perform. Some people in India, squat on the floor and have a bath, so it was important to keep the question. However, many houses may not have a built in bath tub and so was modified as above. In Brazil version [3] of LEFS this item was changed to “Overcoming an obstacle 50 cm high, such as getting into or out of a bathtub.”

The item 5 of original LEFS “Putting on your shoes or socks” was modified to “Putting on your shoes, socks, chappal or sandal” as in Gujarati population the regular use of shoes and socks varies, specifically among females. So, common types of shoe wears were included in that item in Gujarati LEFS.

Considering the use of public transportation in Gujarati population, the item 10 of original LEFS “Getting into or out of a car” was modified to “Getting into or out of a car, rickshaw, bus or train”.

The item 11 of original LEFS “Walking two blocks” was modified to “walking a short distance of about 250 meters” as there is no block system in Gujarat.

The item 12 of original LEFS was “Walking a mile”. The distance measurement was changed from mile to meters as India-Gujarat uses the metric system, most people in Gujarat would not understand the distance a mile represents. So it is converted from 1 mile to the nearly equivalent distance of about 1.5 km. However, in Brazil [3] and Italian [8] version of LEFS, they replaced 1 mile by 1 km.

Item 15 “Sitting for 1 hour” required more discussion among group members regarding its applicability in Gujarati population. In original LEFS the type of sitting is not specified. The most common complaints of lower limbs in Gujarati people was related to cross-sitting on the floor and getting up from that position. So this item was modified accordingly to “Getting up and down from the floor from cross-leg sitting position”. The authors of the Malaysian adaptation [12] also discussed a similar view of it not being clearly specified. The item ‘sitting for one hour’ in the context of Malaysian population may mean sitting on a chair or sitting cross-legged on the floor or even kneeling on the floor. However, as per the Greek version, [2] most of the participants asked for clarification before answering item 15. Specifically, they asked whether they were allowed to stretch their legs while in the seated position or whether their knee joints had to remain in flexion. Since the original LEFS was not specific concerning the proper position of the subjects’ lower limbs, the authors of the Greek version told all participants to answer item 15 according to their own interpretation of the question.

Item 19 of original LEFS “Hopping” was explained as “To move with a small jump either with one foot or both the feet off the ground.”

During the study it was observed that there was a decrease in LEFS scoring with increasing age. It would be more appropriate to do a separate study for different age categories.

Though no statistical analysis was done on relation of pain and function, clinically it was observed that the LEFS score was less with acute and severe pain.

Other studies also suggested the correlation of gender and socioeconomic status with LEFS score. Among them one study [24], concluded that men have higher LEFS score than women and there was no significant correlation with the socioeconomic status and LEFS score.

Future studies should include large sample size including other lower limb conditions. Future research work can also investigate the association of LEFS-Gujarati version with other functional measures.

The translation of the LEFS into a Gujarati version was successful in preserving the semantic and measurement properties of the original version and was shown to be valid and reliable in a Gujarati population.