The Impact of Theory in HPV Vaccination Promotion Research: A Systematic Review and Meta-Analysis.

Objective: Numerous studies examined HPV vaccination promotional strategies. However, an overview of theory use, a synthesis of strategies' effectiveness and an examination of the moderating influence of theory are absent.
Data Source: We retrieved studies from Academic Search Complete, Business Source Complete, PubMed, PsycINFO, Web of Science, CMMC, CINAHL, and MEDLINE.
Study Inclusion and Exclusion Criteria: 1) peer-reviewed articles written in English, 2) experimental or quasi-experimental, 3) measure HPV vaccination-related outcomes, 4) had to contain a control condition and report statistics necessary for conversion (for meta-analysis only).
Data Extraction: 70 and 30 studies were included for the systematic review and meta-analysis respectively.
Data Synthesis: Four major categories were coded: study information, theory use, type of theory, and outcomes. Two independent coders coded the sample (Cohen's Kappa ranged from .8 to 1).
Results: Most of the studies were based in the U.S. (77%, k = 54) with convenient samples (80%, k = 56), targeted toward females (46%, k = 32), and around a quarter did not employ any theories (47%, k = 33). Among theory-driven studies, the most commonly used were Framing (22%, k = 19), Health Belief Model (HBM; 13%, k = 12), and Narrative (7%, k = 6). Among controlled studies, promotional strategies were significantly more effective compared to the control (r+ = .25, p < .001). Strategies guided by the information, motivation, behavioral skills model (IMB) were more effective (r+ = .75, p < .001) than studies guided by framing theory (r+ = -.23, p < .001), HBM (r+ = .01, p < .001), and other theories (r+ = .11, p < .001).
Conclusion: This review contributes to HPV vaccination promotion literature by offering a comprehensive overview of promotional strategies and practical suggestions for future research and practices.