1 “...INTRODUCTION: Although observational studies are increasingly being used to address gaps...”

2 Subjects: “...Observational Studies as Topic...”

3 Subjects: “...Evidence-Based Practice...”

4 Subjects: “...Observational Studies as Topic...”

5 Subjects: “...Literature & literary studies / bicssc...”

6

7 “... controlled trials. However, certain circumstances warrant consideration of observational evidence...”