What are new?
Background
Methods
Original questionnaire
Translation, cross-cultural adaptation and validation of SF 12 into Bengali
Field-testing
Psychometric evaluation of the Bengali SF 12v2
Patients and data collection
Test –retest reliability
Scoring of the SF 12v2 questionnaire
Statistical analysis
Results
Sociodemographic data
Acceptability
Domain | Do not understand | Difficult to understand | Not relevant | Mind answering |
---|---|---|---|---|
General health | 0 | 0 | 0 | 0 |
Physical functioning | 0 | 0 | 0 | 0 |
Role-physical | 0 | 0 | 0 | 0 |
Role emotional | 0 | 0 | 0 | 0 |
Bodily pain | 0 | 0 | 0 | 0 |
Mental health | 0 | 5 (3.84%) | 0 | 0 |
Vitality | 0 | 11(8.46%) | 0 | 0 |
Social functioning | 0 | 0 | 8 (6.15%) | 0 |
Response distribution
Distribution of the SF 12v2 scores
Domain | Range | Mean | SD | Skew ness | Floor effecta (%) | Ceiling effectb (%) |
---|---|---|---|---|---|---|
GH | 0–75 | 26.26 | 17.78 | 0.36 | 20.2 | 2.5 |
PF | 0–100 | 41.70 | 36.87 | 0.34 | 20 | 32.8 |
RP | 0–100 | 43.95 | 27.93 | 0.40 | 10.1 | 7.6 |
RE | 25–100 | 62.18 | 26.21 | -0.06 | 21.8 | 17.6 |
BP | 0–100 | 43.70 | 35.09 | 0.12 | 27.7 | 12.6 |
MH | 0–100 | 57.04 | 27.50 | -0.14 | 2.5 | 7.6 |
VT | 0–100 | 55.67 | 31.80 | -0.24 | 10.1 | 16.8 |
SF | 0–100 | 72.90 | 29.93 | -0.98 | 5 | 40.3 |
Reliability
SF 12v2 summery | Domain | Test retest reliability | Cronbach’s alpha | ||
---|---|---|---|---|---|
Spearman’s correlation | ICC | 95% CI | |||
PCS | General health | 1 | 0.992 | (.989, .994) | |
Physical functioning | 0.999 | 0.996 | (.994, .997) | ||
Role-physical | 0.906 | ||||
Bodily pain | 0.993 | 0.991 | (.988, .994) | ||
Role-emotional | 0.995 | 0.994 | (.991, .996) | ||
MCS | Mental health | ||||
Vitality | 0.995 | 0.995 | (.993, .997) | ||
Social functioning | 0.997 | 0.998 | (.998, .999) | 0.908 | |
0.997 | 0.997 | (.996, .998) | |||
0.992 | 0.994 | (.992, .996) |
Validity
Content validity
Construct validity
Factor analysis
Domain | Component | |
---|---|---|
1 (Physical) | 2 (Mental) | |
General health | 0.84541 | 0.106328 |
Physical functioning | 0.827674 | 0.287226 |
Role-physical | 0.809868 | 0.422559 |
Role emotional | 0.125812 | 0.84526 |
Bodily pain | 0.800717 | 0.424837 |
Mental health | 0.30602 | 0.886262 |
Vitality | 0.511844 | 0.784211 |
Social functioning | 0.295419 | 0.792428 |
Internal construct validity
Correlation between domains | ||||||||
---|---|---|---|---|---|---|---|---|
Scales | General health | Physical functioning | Role physical | Role emotional | Bodily pain | Mental health | Vitality | Social functioning |
General health | 1 | |||||||
Physical functioning | 0.60 | 1 | ||||||
Role-physical | 0.64 | 0.77 | 1 | |||||
Role emotional | 0.29 | 0.38 | 0.5 | 1 | ||||
Bodily pain | 0.65 | 0.68 | 0.86 | 0.38 | 1 | |||
Mental health | 0.43 | 0.49 | 0.54 | 0.74 | 0.6 | 1 | ||
Vitality | 0.54 | 0.6 | 0.68 | 0.64 | 0.78 | 0.9 | 1 | |
Social functioning | 0.28 | 0.49 | 0.64 | 0.57 | 0.6 | 0.70 | 0.71 | 1 |
Convergent and discriminant validity
B.HAQ | General health | Physical functioning | Role physical | Role emotional | Bodily pain | Mental health | Vitality | Social functioning | |
---|---|---|---|---|---|---|---|---|---|
B.HAQ | 1 | ||||||||
GH | -0.717 | 1 | |||||||
PF | -0.813 | 0.601 | 1 | ||||||
RP | -0.821 | 0.643 | 0.771 | 1 | |||||
RE | -0.356 | 0.293 | 0.378 | 0.502 | 1 | ||||
BP | -0.801 | 0.646 | 0.681 | 0.863 | 0.376 | 1 | |||
MH | -0.509 | 0.426 | 0.49 | 0.538 | 0.741 | 0.601 | 1 | ||
VT | -0.669 | 0.544 | 0.602 | 0.677 | 0.636 | 0.783 | 0.904 | 1 | |
SF | -0.484 | 0.277 | 0.49 | 0.641 | 0.568 | 0.6 | 0.703 | 0.71 | 1 |
Discussion
Conclusions
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The translated and culturally adapted Bengali version of SF 12v2 is an acceptable, reliable and valid instrument that can be administered to Bangladeshi patients with Rheumatoid arthritis for evaluation of their function and disability.
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The SF 12vs2 is an instrument to measure generic and specific health related quality of life (HRQoL) in a quick and easy way and it is increasingly being used in clinical trials and health services research.
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We completed the first Bengali version of the questionnaire.
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The Bengali SF12v2 administered by interviewers demonstrated psychometric properties similar to the original US English version and translations in other languages.
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With about 178 million in Bangladesh and about 261.5 million total speakers worldwide, Bengali it is the sixth most spoken language in the world, so it is important that this questionnaire is now available for studies in this parts of India and Bangladesh.
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The questionnaire should be evaluated and used in people from the general population and in patients with different medical conditions to assess and compare the health status and impact of different disorders in Bengali speaking patients.