Development and validation of an HPV infection knowledge assessment scale among Aboriginal and Torres Strait Islander Peoples.

Background: An increased incidence of Human Papillomavirus (HPV) infection and its related cancers has been observed in recent years. Correct knowledge about HPV infection can lead to a significant decrease in transmission and a subsequent increase in vaccine uptake. Awareness and behavioural perception towards HPV infections are critical for improving HPV vaccination rates among Aboriginal and/or Torres Strait Islander Peoples. However, to the best of our knowledge, there has been no instrument designed to measure knowledge about HPV infection that is culturally appropriate and validated among Aboriginal and/or Torres Strait Islander People.

Aim: To address this research gap, this paper aims to examine the psychometric properties of the HPV Knowledge Tool (HPV-KT) in an Indigenous population sample from South Australia.

Methodology: Data from 747 Indigenous Australian Adults who participated in the 12-month follow-up of the HPV and Oropharyngeal Carcinoma in Indigenous Australians Study was utilised for this study. The psychometric properties examined included1) dimensionality and item redundancy; (2) network loadings; (3) model fit; (4) criterion validity; and (5) reliability. The network model was estimated using the Graphical Least Absolute Shrinkage and Selector Operator (GLASSO). Evaluation of the HPV-KT (10 items) dimensionality and item redundancy was conducted within the framework of Exploratory Graph Analysis (EGA). Reliability was evaluated with the McDonald's Omega (ω) coefficient.

Results: After the exclusion of two items, the HPV-KT exhibited good psychometric properties for Aboriginal and/or Torres Strait Islander Peoples. The two dimensions of "General HPV Knowledge" and "Commonness of HPV" were identified. The dimension of "Commonness of HPV" displayed poor reliability, so a sum score for this subscale is not recommended (i.e. the items can still be used individually) The network model of the 7-item HPV-KT was fitted in the validation sample and model fit was adequate (x2 (7) = 17.17, p < 0.016; CFI = 0.980; TLI = 0.94; RMSEA = 0.063, 90% CI = 0.025-0.010). Furthermore, the reliability of the "General HPV Knowledge" subscale (ω = 0.76, 95% CI: 0.72-0.79), while the reliability of the "Commonness of HPV" subscale (ω = 0.58, 95% CI0.58-0.88) was poor.

Conclusion: The HPV-KT was adapted for an Aboriginal and/or Torres Strait Islander population and is readily available for future use in Australia. The addition of items assessing specifications of HPV infection, natural history and behaviour will improve the reliability and usability to assess the level of accurate knowledge about HPV infection. Future studies should investigate the possibility of developing new items for the dimension 'Commonness of HPV'.