Ensuring a successful transition from Pap to HPV-based primary cervical cancer screening in Canada by investigating the psychosocial correlates of women’s intentions: Protocol for an observational study (Preprint)

The validity of instruments to measure knowledge in population-based cancer screening targeting individuals at average risk - A systematic review

OBJECTIVES

Relevant knowledge is essential for informed choices about (non)participation in population-based cancer screening. Many instruments have been proposed to assess residents' knowledge about cancer screening programmes but their measurement properties are unknown. This systematic review aims to identify and critically evaluate the measurement properties of instruments to measure knowledge about cancer screening in individuals eligible for population-based screening.

METHODS

A literature search was undertaken in PubMed, PsycINFO, Embase, CINAHL, Scopus and Web of Science in August 2023. The review included any study reporting one or more measurement properties of the questionnaire or sub-scale used measuring knowledge of cancer screening including breast, colorectal and/or cervical cancer screening. Studies including males aged 45 or older and females aged 20 or older were included. Two independent reviewers screened the articles and assessed the included articles using the COnsensus-based Standards for the selection of health Measurement Instruments (COSMIN).

RESULTS

We included 24 instruments, which varied in number and characteristics of items. All instruments were assessed as having an inadequate instrument development. The results of structural validity, internal consistency, criterion validity and reliability were assessed as indeterminate, while construct validity and responsiveness were assessed as sufficient.

CONCLUSION

This systematic review identified no instruments to measure knowledge about cancer screening where the measurement properties were sufficiently evaluated. There is a lack of focus on content validity and structural validity, and further validation of the instruments is needed. The results indicate a lack of shared understanding or agreement of what constitutes relevant knowledge about cancer screening.

Are Canadian Women Prepared for the Transition to Primary HPV Testing in Cervical Screening? A National Survey of Knowledge, Attitudes, and Beliefs

As Canadian provinces and territories prepare to transition to HPV-based primary screening for cervical cancer, failure to identify and address potential barriers to screening could hinder program implementation. We examined screening-eligible Canadians' attitudes towards and knowledge of cervical screening. A nationally representative sample of screening-eligible Canadians (N = 3724) completed a web-based survey in the summer of 2022. Oversampling ensured that half of the sample were underscreened for cervical cancer (>3 years since previous screening or never screened). The participants completed validated scales of cervical cancer, HPV, and HPV test knowledge and HPV test and self-sampling attitudes and beliefs. Between-group differences (underscreened vs. adequately screened) were calculated for scales and items using independent sample t-tests or chi-square tests. The underscreened participants (n = 1871) demonstrated significantly lower knowledge of cervical cancer, HPV, and the HPV test. The adequately screened participants (n = 1853) scored higher on the Confidence and Worries subscales of the HPV Test Attitudes and Beliefs Scale. The underscreened participants scored higher on the Personal Barriers and Social Norms subscales. The underscreened participants also endorsed greater Autonomy conferred by self-sampling. Our findings suggest important differential patterns of knowledge, attitudes, and beliefs between the underscreened and adequately screened Canadians. These findings highlight the need to develop targeted communication strategies and promote patient-centered, tailored approaches in cervical screening programs.

Understanding the Challenges of HPV-Based Cervical Screening: Development and Validation of HPV Testing and Self-Sampling Attitudes and Beliefs Scales

The disrupted introduction of the HPV-based cervical screening program in several jurisdictions has demonstrated that the attitudes and beliefs of screening-eligible persons are critically implicated in the success of program implementation (including the use of self-sampling). As no up-to-date and validated measures exist measuring attitudes and beliefs towards HPV testing and self-sampling, this study aimed to develop and validate two scales measuring these factors. In October-November 2021, cervical screening-eligible Canadians participated in a web-based survey. In total, 44 items related to HPV testing and 13 items related to HPV self-sampling attitudes and beliefs were included in the survey. For both scales, the optimal number of factors was identified using Exploratory Factor Analysis (EFA) and parallel analysis. Item Response Theory (IRT) was applied within each factor to select items. Confirmatory Factor Analysis (CFA) was used to assess model fit. After data cleaning, 1027 responses were analyzed. The HPV Testing Attitudes and Beliefs Scale (HTABS) had four factors, and twenty-two items were retained after item reduction. The HPV Self-sampling Attitudes and Beliefs Scale (HSABS) had two factors and seven items were retained. CFA showed a good model fit for both final scales. The developed scales will be a valuable resource to examine attitudes and beliefs in anticipation of, and to evaluate, HPV test-based cervical screening.

Development and validation of the cervical cancer knowledge scale and HPV testing knowledge scale in a sample of Canadian women

Knowledge of cervical cancer and HPV testing are important factors in proactive and continued engagement with screening and are critical considerations as countries move towards the implementation of HPV-based primary screening programs. However, existing scales measuring knowledge of both cervical cancer and HPV testing are not up to date with the current literature, lack advanced psychometric testing, or have suboptimal psychometric properties. Updated, validated scales are needed to ensure accurate measurement of these factors. Therefore, the aim of this study was to develop and validate two scales measuring cervical cancer knowledge and HPV testing knowledge. A pool of items was generated by retaining relevant existing items identified in a 2019 literature search and developing new items according to themes identified in recent systematic reviews. Items were assessed for relevance by the research team and then refined through seven cognitive interviews with Canadian women. A web-based survey including the remaining items (fourteen for each scale development) was administered to a sample of Canadian women in October and November of 2021. After data cleaning, N = 1027 responses were retained. Exploratory and Confirmatory Factor Analysis were conducted, and Item Response Theory was used to select items. The final cervical cancer knowledge scale (CCKS) and HPV testing knowledge scale (HTKS) were unidimensional, and each consisted of eight items. CFA demonstrated adequate model fit for both scales. The developed scales will be important tools to identify knowledge gaps and inform communications about cervical cancer screening, particularly in the context of HPV-based screening implementation.

Assessing Canadian women's preferences for cervical cancer screening: A brief report

Human papillomavirus (HPV) testing is recommended for primary screening for cervical cancer by several health authorities. Several countries that have implemented HPV testing programs have encountered resistance against extended screening intervals and older age of initiation. As Canada prepares to implement HPV testing programs, it is important to understand women's preferences toward cervical cancer screening to ensure a smooth transition. The objective of this study was to assess Canadian women's current preferences toward cervical cancer screening. Using a web-based survey, we recruited underscreened ( > 3 years since last Pap test) and adequately screened (< 3 years since last Pap test) Canadian women aged 21–70 who were biologically female and had a cervix. We used Best-Worst Scaling (BWS) methodology to collect data on women's preferences for different screening methods, screening intervals, and ages of initiation. We used conditional logistic regression to estimate preferences in both subgroups. In both subgroups, women preferred screening every three years compared to every five or ten years, and initiating screening at age 21 compared to age 25 or 30. Adequately screened women (n = 503) most preferred co-testing, while underscreened women (n = 524) preferred both co-testing and HPV self-sampling over Pap testing. Regardless of screening status, women preferred shorter screening intervals, an earlier age of initiation, and co-testing. Adequate communication from public health authorities is needed to explain the extended screening intervals and age of initiation to prevent resistance against these changes to cervical cancer screening.