Material and Method: The Barthel Index (BI) was translated into Thai using a forward-backward translation protocol. Fifty-three patients with low-energy femoral neck fracture were then prospectively enrolled and evaluated with TVBI, the de Morton Mobility Index (DEMMI), the EuroQol-5D (EQ-5D), the two-minute walk test (2MWT), and the timed get-up-and-go test (TUG) within 2 weeks after surgery. Validity of TVBI was assessed by calculating the index of item-objective congruence and correlating TVBI scores with scores from other outcome measurements. TVBI reliability was evaluated by measuring test-retest reliability and internal consistency.

Results: TVBI had high content validity and strong correlation with DEMMI (Spearman’s rho = 0.629; p-value <0.001), and moderate correlation with EQ-5D utility score, EQ-5D visual analog scale, and 2MWT (Spearman’s rho = 0.452, 0.313, and 0.413, respectively; p-value <0.05). Interobserver and intraobserver reliabilities of TVBI were high, with intraclass correlation coefficients of 0.714 and 0.968, respectively. The internal consistency of TVBI was acceptable (Cronbach’s alpha = 0.694).

Conclusion: TVBI yields good validity and reliability, is without floor or ceiling effects, and can be used in all patients during early postoperative treatment after femoral neck fracture.

Keywords: Barthel index, femoral neck fracture, osteoporosis, reliability, validity