The purposes of this study were to conduct cross-cultural adaptation of the Functional Rating Index (FRI), to test psychometric properties of the translated questionnaire and to examine head-to-head comparisons with other questionnaires.

This study comprised 2 major stages: 1) Cross-cultural adaptation and 2) psychometric properties testing.

Cross-cultural adaptation stage:

The FRI was cross-culturally adapted to Thai following the well-accepted guideline for the process of cross-cultural adaptation of self-report measure.

Psychometric properties testing stage:

The patients with back or neck pain completed the questionnaires at the first visit, the second visit and at 2-week (or at discharge or when reporting 80% improvement from the first visit).

Inclusion Criteria

The participants were eligible if they were:

1. aged 18 years or older
2. seeking physical therapy treatment for a complaint of back and/or neck pain
3. able to understand, read, speak and write Thai

Exclusion Criteria:

The participants who were not willing to take part in the study, unable to understand, read, speak and write Thai were excluded from this study.

From physical therapy department in 9 settings in Thailand