Construct validity and reliability of the BARRIERS scale in the Spanish context

Objective

To establish the construct validity of the Spanish version of the BARRIERS scale.

Method

Methodological study of validation of a measurement instrument based on data from previously published studies. The study population consisted of nurses from the Basque Health Service and the Canary Health Service. The following variables were extracted and unified: Years of professional experience, possession of a specialist nursing degree, possession of a doctorate, type of activity performed by the professional and field of work. For construct validation, a confirmatory factor analysis (CFA) was performed based on the initial model proposed for the scale and RASCH analysis. A polychoric correlation matrix, factor extraction by unweighted least squares and PROMIN oblique rotation were used. For the RASCH analysis, the Joint Maximun Likelihood estimation (JMLE) method was used; the fit of the items and persons were estimated by means of outfit - Unweighted Mean Square fit statistic (UMS) and infit -Weighted Mean Square Fit Statistic (WMS), as well as the reliability and separation of items and persons.

Results

A total of 1200 nurses and midwives made up the final validation sample (n = 1200), with a mean professional experience of 21.22 ± 9.26 years. The CFA presented a good fit to the data (KMO = 0.935 [95% CI: 0.921-0.945]), changing the factorial assignment in 6 items, while 5 items received factorial scores in more than one factor. The fit values for the 4-factor solution were RMSEA = 0.026 [95% CI: 0.026-0.027] and GFI = 0.991 [95% CI: 0.986-0.991]. In the RASCH analysis most items presented infit-WMS and outfit-UMS values with a good fit.

Conclusions

The Spanish version of the BARRIERS scale has adequate construct validity although there are changes in the assignment of items to the dimensions compared to the original model. The RASCH analysis indicates adequate fit for both persons and items.