The search strategy identified 9405 studies. Five thousand five hundred and forty-two studies were screened for eligibility, and 156 were assessed in full text. Seventy-five studies were selected for inclusion. In addition, two studies were included via a search in gray literature. A total of 77 studies were included in the review. The PRISMA flow diagram is presented in Fig. 1.

PRISMA flow diagram of the selection process

The 77 included studies [36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111] comprised 34 instruments measuring EBP attitudes, behavior or self-efficacy, alone or combined. Twenty-four instruments measured EBP attitudes, 21 measured behavior, and 16 measured EBP self-efficacy. Most instruments were multidimensional and included different subscales (n = 25). Eight instruments were unidimensional, and two had indeterminate dimensionality. Nurses were most frequently represented in the included studies (n = 53), followed by physiotherapists (n = 19), occupational therapists (n = 10), medical doctors (n = 14), mental health workers (n = 16), and social workers (n = 7). Ten of the included instruments had been validated in three or more healthcare disciplines [36, 45, 56, 66, 68, 81, 85, 89, 111]. Seven instruments had been validated in two healthcare disciplines [47, 62, 63, 73, 75, 76, 82] and 17 had been validated in only one discipline [48, 64, 65, 71, 78,79,80, 87, 93, 95, 96, 102, 105, 107, 109, 110]. Details of the included studies and participants are presented in Additional file 3.

Of the 77 studies included, 33 focused on instrument development and 18 focused on content validity on already developed instruments. Table 1 summarizes the quality assessment, rating, and quality of evidence on the development and content validity per instrument.

The quality of concept elicitation (development of items) was rated as “adequate” in three studies [85, 93, 107], where a clearly reported and appropriate method was used and a sample representing the target population was involved. A further 19 studies received a “doubtful” quality rating [36, 45, 47, 48, 62, 66, 68, 76, 78, 80,81,82, 89, 95, 96, 105, 108,109,110]. Some of these studies used qualitative methods to generate items, but the method, or parts of it, was not clearly described. In other studies, it was doubtful whether the included sample was representative of the target population, and some used quantitative methods. Some studies were rated as “doubtful” if it was stated that authors of these studies had talked or discussed the items with relevant healthcare professionals as a part of concept elicitation, but it was doubtful whether this method was suitable. Finally, 12 studies received an “inadequate” quality rating for concept elicitation [56, 63,64,65, 71, 73, 79, 87, 102,