Validation of the Portuguese version of the Evidence-Based Practice Questionnaire

OBJECTIVES: to describe the process of translation and linguistic and cultural validation of the Evidence Based Practice Questionnaire for the Portuguese context: Questionário de Eficácia Clínica e Prática Baseada em Evidências (QECPBE). METHOD: a methodological and cross-sectional study was developed. The translation and back translation was performed according to traditional standards. Principal Components Analysis with orthogonal rotation according to the Varimax method was used to verify the QECPBE's psychometric characteristics, followed by confirmatory factor analysis. Internal consistency was determined by Cronbach's alpha. Data were collected between December 2013 and February 2014. RESULTS: 358 nurses delivering care in a hospital facility in North of Portugal participated in the study. QECPBE contains 20 items and three subscales: Practice (α=0.74); Attitudes (α=0.75); Knowledge/Skills and Competencies (α=0.95), presenting an overall internal consistency of α=0.74. The tested model explained 55.86% of the variance and presented good fit: χ2(167)=520.009; p = 0.0001; χ2df=3.114; CFI=0.908; GFI=0.865; PCFI=0.798; PGFI=0.678; RMSEA=0.077 (CI90%=0.07-0.08). CONCLUSION: confirmatory factor analysis revealed the questionnaire is valid and appropriate to be used in the studied context.


Introduction
Evidence-based practice is defined as a process in which nurses make clinical decisions using the best scientific evidence available, their clinical experience and patients' preferences in the context of resources available (1) . A large systematic review conducted in 2004 (2)  incorporating evidence into clinical practice and these processes have been the focus of attention (8) in the construction of assessment instruments. Specifically referring to the Evidence Based Practice Questionnaire, developed by Upton & Upton (9) in 2006, information and opinions concerning the use of evidence-based practice were gathered from healthcare workers. Validating it to enable its generalized use is important since this instrument is currently recurrent in multiple contexts and there is, in addition to its original version in English, a Spanish version (10)  The following criteria were utilized in the confirmation of the number of factors (11) : (1)  values (12)(13) . Local goodness of fit was assessed using factor loads and the individual reliability of items.
The GFI, AGFI and CFI should be close to 0.90, while the recommended RMSEA is up to 0.08 (12)(13) . Model fitting to the theoretical considerations went beyond the modification indices.

Results
Most participants (n=358) were female (78%), aged between 30 and 39 years old (48.0%), and 49% had earned a bachelor's degree in nursing less than four years ago (year of graduation ≥ 2011) ( Table 1). The instrument is composed of 24 items and admits only one out of seven possible responses. The number of participants was intended to fully meet the requirements concerning sampling size, as well as power and reliability criteria (14)     Given the various analyses performed, Figure   1 presents

Discussion
According to the results, the QECPBE-20's threefactor model presents empirical evidence for its use in regard to construct validity, as well as in regard to reliability analysis of latent variables. Comparing the analysis of the Portuguese version with the original questionnaire (9) and the Spanish version (10) , we verified Similarly, the barriers against EBP are ignored in this instrument, even though significant importance is given to the incorporation of effective evidence-based nursing practice (6) , due to personal, professional, academic or organizational factors. Hence, the use of QECPBE-20 should be complemented by other instruments that are validated and available for the Portuguese context (15,17) .
The joint application of instruments will enable the assessment of methodological competencies regarding EBP and allow its use in other spheres, related to education at this level and to the implementation of programs encouraging the integration of evidence with I. Tendo em conta a sua prática em relação aos cuidados prestados aos doentes (clientes) no último ano, com que frequência, em consequência de uma lacuna no seu conhecimento (assinale com √ ou com X), fez o seguinte:  the delivery of care. On the other hand, these instruments can help outline the profile of workers required to make decisions (18) , while these workers should always ground their practice on the best scientific knowledge available.
In this regard, and as already shown (18)(19) , in order to perform safely and professionally, nurses require more knowledge, improved skills, and should be effectively confident when making decisions. As nurses gain confidence in their practice, they tend to know better how to incorporate research knowledge into practice.
Another aspect that should be further considered is related to the potential limitation brought by the context of the professional practice of the nurses addressed in this study; even though it is very significant and part of an academic context, is centered on a single hospital facility.
Hence, further studies are needed, conducted in other contexts, such as primary healthcare, to verify whether the results are in agreement or not, as there are differences in terms of EBP from an organizational perspective.

Conclusion
The analysis showed empirical evidence regarding the questionnaire and it is valid and appropriate to be