Invasive cervical cancer (ICC) is almost entirely treatable if found early through cervical cancer screening, yet many women remain underscreened or never screened.1 2–4 5 6 7 8 self-efficacy , as they relate to Pap testing adherence in this population.
Perceived barriers and self-efficacy are concepts from behavioral theories such as the Theory of Reasoned Action, Theory of Planned Behavior, and Health Belief Model9,10 11–13 14 self-efficacy is confidence in one’s ability to complete the screening.15 16,17 self-efficacy scale scores are related to screening adherence.14,18 self-efficacy have been tailored according to participant survey input in previous studies and could be tailored in similar interventions to increase Pap testing in Black women.16,17,19
In this regard, current barriers and self-efficacy scales already exist. Specifically, barriers scales have been tested among Hispanic and Korean American women, and a self-efficacy scale was validated among Black women for mammography.11,13,20 α = .68) for Pap testing was tested among Hispanic women.20 20 13 α = .83) showed lower barrier scores on individual items (cost, uncomfortableness with a male provider, and preference for Korean medicine) in the action/maintenance stage as opposed to the precontemplation/relapse stages.13 self-efficacy scale (Cronbach’s α = .88) was tested and validated among Midwestern Black women in various community and clinical settings.11
Although current barriers and self-efficacy scales exist, there is a gap in the literature in relation to validation of these scales specifically in Pap testing of Black women. While the barriers scale (validated in Hispanic women) of Byrd et al20 13 self-efficacy scale of Champion et al11
Researchers face 2 options when measuring concepts; they can either modify existing instruments or develop new instruments if current instruments do not adequately measure a concept. Given that many issues and confidences related to screening are similar among cultures and screening tests,11,13,20 self-efficacy items may need to be added to a self-efficacy for Pap testing scale such as overcoming embarrassment because the nature of Pap test may be more embarrassing than a mammogram. The use of invalid instruments for Black women could lead to ineffective cervical cancer screening interventions in a population that bears a greater burden of cervical cancer.
The purpose of the current study was to modify and test existing barriers and self-efficacy scales among Black women that would be relevant for Pap testing behavior by adapting Champion’s mammography theoretical framework and items from previous scales and the literature.11,13,20–23 self-efficacy on Pap testing adherence is important in intervention development and clinical decision-making.
Our research hypotheses for reliability and validity of each scale include the following:
internal consistency reliability will be 0.7 or greater;
exploratory factor analyses will reveal a unidimensional latent variable for each scale (barriers and self-efficacy ); and
barriers and self-efficacy will be significantly related to screening adherence when controlling for antecedent variables (age, education, income, marital status, provider recommendation, Pap testing reminder, and history of abnormal Pap test).
Conceptual Framework
The conceptual model (Figure ) for the current study was modified from previous health behavior models used when developing items for mammography scales.11 24 24,25 25 26 27 28 29,30 self-efficacy . The outcome is on the right-hand side and is Pap testing adherence (whether participants had a Pap test in the previous 3 years).
Figure: Conceptual model.
Methods
Sample
Our sample (n = 118) was drawn from women who attended the 2018 Annual Indiana Black Expo, a large African American cultural event that includes a health fair component. Our sample size was based on convenience (how many women responded to the survey); however, for our primary goal of assessing validity, a sample size of n = 118 met the goal for an exploratory factor analysis of having at least 5 respondents per item.31 8
Approach
The researchers had a booth at the health fair that advertised a research study about cervical cancer screening. Individuals who were interested in participating in the study approached the investigator and a research assistant. After determining eligibility, participants who wanted to continue completed a computer survey administered on REDCap or paper surveys and then were given a $20 Wal-Mart gift card. The research was conducted over a 3-day period in July 2018. The Indiana University institutional review board approved the study procedures.
Measures
Antecedent (age, education, income, marital status, provider recommendation, and Pap testing reminder) measures were adapted from Champion’s prior studies. Age was measured on a continuous scale from 30 to 65. Education was measured as a categorical variable as either less than a 4-year degree or a 4-year degree or more. Income was measured as a categorical variable and divided into whether participants reported a yearly income of less than $30 000 or $30 000 or more. Marital status was measured in 2 categories as either married (or partnered) or divorced (or widowed). Provider recommendation of a Pap test and Pap testing reminder were measured as yes/no items.
Items in the scales for the theoretical variables (barriers and self-efficacy ) were adapted from previous instruments and variables from the literature that have predicted Pap test adherence. After determining the items to include in the perceived barriers and self-efficacy instruments, the items were reviewed for face validity by 5 Black lay women between the ages of 21 and 65 years who were not health professionals or researchers. The investigator asked each woman to judge the items for relevance, clarity, and inclusiveness of Pap testing issues. The women suggested minor wording changes. As a next step to establish content validity, content experts, including 2 PhD-prepared behavioral theory researchers, judged items for relevance and clarity. The 2 content experts rated items and recommended deletion of 3 barriers items and 2 self-efficacy items.
Eleven barrier items were adapted from scales used for Hispanic and Korean American women and issues related to Pap testing in the literature.13,20 13,20 21,32 23 33 22,34
Our 12 self-efficacy items were adapted from Champion’s self-efficacy for mammography and from the literature.11 self-efficacy for mammography scale included getting a Pap test even if the doctor does not tell one to, one does not know what to expect, or one is worried; finding room in one’s schedule for, transportation to, a way to pay for, and a place to get a Pap test; being able to deal with people at the clinic and make an appointment for a Pap test; and getting a Pap test if one really wants to.11 33
The theoretical variables were placed on a 5-point Likert scale from strongly disagree to strongly agree. Item responses within each scale were summed and coded such that a higher score indicated higher barriers and a higher score indicated higher self-efficacy . The outcome measure of Pap testing adherence in the past 3 years (yes/no) was based on USPTSF cervical cancer screening guidelines.
Reliability
All analyses were conducted in IBM SPSS Statistics Version 26. Internal consistency reliability for both barriers and self-efficacy scales was measured with Cronbach’s α coefficients. Item analysis was completed with inter-item correlations and corrected item-total correlations.
Validity
First, discriminant (construct) validity was measured through exploratory factor analysis with the principal component analysis extraction method. Squared multiple correlations were specified as the initial estimates of communalities. Varimax rotation was used with 2 factors selected, and factor loadings of 0.4 or greater were considered adequate. Second, 2 separate logistic regression models with antecedents and barriers and then antecedents and self-efficacy were regressed on Pap test adherence behavior.
Results
The sample included 118 Black women who completed the survey. Table 1 describes the sample characteristics. Compared with the national US Black population, the Black women who completed this survey were slightly older (average age of 36 vs. 45 years) and had higher educational levels (24% vs. 42% had a 4-year degree or more).35 35 35
Table 1 -
Demographic Characteristics (n = 118)
Characteristic
n or Mean
% or SD
Age
45
12
Education
<4-y college degree
70
58
≥4-y college degree
51
42
Income
26
21
<$30 000 a year
41
35
≥$30 000 a year
77
65
Marital status
Married or partner
42
35
Divorced, widowed, separated, or single
77
65
Physician recommendation
90
74
No
31
26
Pap test reminder
Yes
49
60
No
72
40
History of abnormal Pap test
Yes
70
58
No
51
42
Abbreviations: n, number in sample; Pap, Papanicolaou.
Reliability
First, the correlation matrix of the 11 items in the barriers scale was analyzed. Individual items were assessed in the correlation matrix for high inter-item correlations (>0.7), indicating redundancy. Inter-item correlations ranged from 0.081 to 0.841. Items considered redundant (inter-item correlation >0.7) were removed including “A Pap test is too expensive” and “I do not have time for a Pap test.” After elimination of these items, corrected item-total correlations greater than 0.7 and less than 0.4 were removed. These items included “I am afraid a Pap test will find cancer,” “I could not afford the follow-up to an abnormal Pap test,” and “I do not have transportation to get a Pap test.” After removal of these items, internal consistency reliability obtained a Cronbach’s α of .79, inter-item correlations ranged between 0.298 and 0.580, and corrected item-total correlations were from 0.479 to 0.628, all within hypothesized ranges.36
Next, internal consistency reliability for self-efficacy was analyzed. Inter-item correlations ranged from 0.294 to 0.886. Items considered correlated highly (inter-item correlation >0.7) with other items included “I can deal with the people at the clinic where I would get a Pap test,” “I can get a Pap test even if a doctor does not tell me to,” “I can find a place to get a Pap test,” “I can get a Pap test even if I do not know what to expect,” “I can find a way to pay for a Pap test,” and “I can get transportation to the clinic for a Pap test.” After elimination of these items, the value for Cronbach’s α was .85, inter-item correlations ranged from 0.313 to 0.664, and item-total correlations were between 0.560 and 0.697. The mean for the final self-efficacy was 27.24 (SD, 3.04) with a range of 20 to 30. The item-total correlations and means for the final barriers and self-efficacy scales are shown in Table 2 .
Table 2 -
Corrected Item-Total Correlation Coefficients and Item Loadings for Exploratory Factor Analysis
Item
Correlation
X
−
Factor Loading
Barriers
It is embarrassing to have a Pap test.
0.628
2.35
0.781
A Pap test will be painful.
0.598
2.60
0.758
I do not want to step on a scale at the clinic.
0.531
2.27
0.662
I have difficulty remembering to make an appointment for a Pap test.
0.515
2.02
0.619
I do not know the purpose of the Pap test.
0.562
1.92
0.702
I would not want a male provider to examine me.
0.479
2.84
0.668
Self-efficacy
I can make room in my schedule for a Pap test.
0.697
4.63
0.823
I can get a Pap test even if I am worried.
0.648
4.50
0.771
I can make an appointment for a Pap test.
0.682
4.49
0.828
I can get a Pap test if I really want to.
0.688
4.56
0.824
Even if it’s embarrassing, I could get a Pap test.
0.637
4.61
0.764
I can find the time for a Pap test.
0.560
4.45
0.709
Abbreviation: Pap, Papanicolaou.
Validity
First, exploratory factor analysis was conducted on each scale, with the 2 factors accounting for 36% of the variance. The 2 factors represented eigenvalues of 4.335 and 2.591, which were greater than 1. All items loaded on their respective factors. Barriers items loaded on factor 1 with high loadings from 0.619 to 0.781 (>0.4 threshold) (Table 2 ). Self-efficacy items loaded on factor 2 with loadings between 0.709 and 0.828 (Table 2 ). Items did not overlap between scales, that is, after loading on a primary scale, the same item did not load greater than 0.3 on the other scale. The Kaiser-Meyer-Olkin Measure of Sampling Adequacy was 0.789 with a Bartlett’s test of sphericity of 0.001.
Next, Pap testing adherence was regressed on antecedents and barriers and then antecedents and self-efficacy (Tables 3 and 4 ). All control variables (age, education, income, physician recommendation, Pap test reminder, and history of abnormal Pap test) were entered into the regression models. The logistic regression model found significant odds ratios for Pap testing reminder and barriers when regressed on Pap testing adherence. The barriers model estimated the odds of obtaining a Pap test increased 3.28 (confidence interval [CI], 1.103–9.78) times if a woman received a Pap testing reminder and decreased 0.896 (0.807–0.995) times for every unit increase in the barriers scale. The logistic regression model found significant odds ratios for Pap testing reminder and self-efficacy when regressed on Pap testing adherence. The self- efficacy model estimated that the odds of obtaining a Pap test increased 10.74 (CI, 1.87–12.04) times if a woman received a Pap testing reminder and 1.19 (CI, 1.00–1.42) times for every unit increase in the self-efficacy score.
Table 3 -
Barriers Logistic Regression Model Predicting Pap Testing Adherence
Variable
B
χ
2
P
OR
95% CI
Age
0.020
0.821
.365
1.020
0.977–1.065
<4-y college degree
0.267
0.210
.647
0.766
0.244–2.400
≥4-y college degree
Ref
Ref
Ref
Ref
Ref
<$30 000 a year
−0.511
0.550
.458
1.668
0.432–6.438
≥$30 000 a year
Ref
Ref
Ref
Ref
Ref
Single, divorced, separated, or widowed
−0.063
0.011
.915
1.065
0.334–3.396
Physician recommendation
0.496
0.783
.376
0.609
0.203–1.827
Pap test reminder
1.188
4.563
.033
3.280
1.103–9.757
History of abnormal Pap test
0.885
2.037
.153
2.424
0.719–8.177
Barriers
−0.110
4.182
.041
0.896
0.807–0.995
Notes: df = 1. Model χ 2 = 17.041, df = 8, P < .030.
Abbreviations: B , coefficient; CI, confidence interval; OR, odds ratio; Pap, Papanicolaou; Ref, reference.
Table 4 -
Self-efficacy Logistic Regression Model Predicting Pap Testing Adherence
Variable
B
χ
2
P
OR
95% CI
Age
0.016
0.524
.469
1.016
0.973–1.060
<4-y college degree
−0.047
0.006
.937
1.048
0.329–3.341
≥4-y college degree
Ref
Ref
Ref
Ref
Ref
<$30 000 a year
−0.579
0.713
.398
1.784
0.466–6.833
≥$30 000 a year
Ref
Ref
Ref
Ref
Ref
Single, divorced, separated, or widowed
−0.064
0.012
.915
1.066
0.331–3.429
Physician recommendation
0.795
1.972
.160
0.452
0.149–1.370
Pap test reminder
1.278
5.521
.019
10.737
1.870–12.041
History of abnormal Pap test
0.591
0.941
.332
0.554
0.168–1.829
Self-efficacy 0.176
3.918
.048
1.193
1.002–1.420
Notes: df = 1. Model χ 2 = 17.892, df = 8, P < .022.
Abbreviations: B , coefficient; CI, confidence interval; OR, odds ratio; Pap, Papanicolaou; Ref, reference.
Discussion
The current study evaluated the internal consistency reliability and validity of 2 instruments, perceived barriers and self-efficacy to Pap testing, among Black women. Both the barriers and self-efficacy scales supported high internal consistency reliability and construct validity. Several items were removed from each scale to improve item correlations and reliability for each scale. Discriminant validity was supported in exploratory factor analysis and construct validity with the hypothesized relationships of barriers and self-efficacy with Pap testing adherence. Exploratory factor analysis showed the unidimensionality of both scales and factor loadings of greater than 0.4 on each item. In the logistic regression models, Pap testing reminder, barriers, and self-efficacy were found to be associated with Pap testing adherence. Age, education, income, marital status, physician recommendation, and history of abnormal Pap test were not significant. These variables have been found to be significant in other studies; however, they deserve further testing with a larger sample.
Limitations of previous barriers and self-efficacy scales are that they have not been validated in Black women or with Pap testing behavior. In addition, our barriers scale is unique from the previous barriers scales13,20 α of our barriers scale was .79, which was higher than that of the Byrd scale (.68)20 13 self-efficacy scale was validated similarly to our scale through exploratory factor analysis and through multiple linear regression.11 α was .85 compared with Champion’s Cronbach’s α of .88.11
The final set of items in our barriers scale contained items that overlapped with the Byrd and Tung barriers scales, as well as items that reflected Black women’s specific issues with Pap testing.13,20 13 23 33 21,32
The final set of items in our self-efficacy scale consisted of 4 items adapted from Champion’s self-efficacy scale and 2 items from the literature. Our items adapted from Champion’s scale included making room in one’s schedule for Pap test, getting a Pap test even if one is worried, making an appointment for a Pap test, and getting a Pap test if one really wants to.11 33
Interventionists and health professionals could use the barriers scales from this study to build interventions to increase Pap testing. Interventionists could use the barriers scale to identify women’s barriers to Pap testing and then tailor their messaging to encourage women to overcome their specific barriers. For example, if a woman scored highly on the barrier item embarrassment, interventionists could evaluate the sources of her embarrassment and then make efforts to modify these factors. As an example, interventionists could suggest to women that they could ask for appropriately sized equipment (eg, gowns and speculums) or to keep more of the body covered during the Pap test. Furthermore, teaching relaxation techniques to some women may help them to feel more relaxed and less embarrassed. Health professionals could target Black women, a population more likely to suffer morbidity and mortality from cervical cancer, with reminders for Pap testing, and ask about their specific barriers at an appointment if they are overdue for Pap testing.
Interventionists and health professionals could use the self-efficacy scale to identify specific self-efficacy items that women score lower on. Learning that another person completed a related behavior, in this instance Pap testing, could help an individual believe that she is also capable of performing Pap testing.15
At 6 items for the barriers scale and 6 for the self-efficacy scale, these are short scales that could easily be implemented in future research, including intervention studies. Barriers, self-efficacy , and mailed/telephone Pap testing reminders may play an important role in Pap testing adherence for Black women and are critical components for interventionists and providers when considering types of interventions and the framing of messages around Pap testing. Other measures have been found to be associated with Pap testing and other screening behaviors that should be considered in the future when testing these scales include other health beliefs (perceived benefits and susceptibility),11 29,37 20 5 38
Limitations
The participants in this study were recruited from a minority health fair in a single city, which may limit generalizability. Women who attend a health fair may be more educated and likely to engage in health-seeking behaviors. Our sample was an urban population, and rural Black populations may face more logistical barriers to Pap testing such as nearby availability of a clinic. Although we included 118 participants, these scales should be tested in a larger, more representative population. Subpopulations within racial and ethnic groups can vary, so it is important to validate these scales with other subgroups of Black women for conceptual and scale equivalence, as well as with women representing other races and ethnicities. As more women are screened through HPV testing, these scales may need to be reevaluated as screening issues may change. The outcome of this study did not include cotesting with Pap and HPV testing, so possibly many of the women who stated that they did not have a Pap test in the past 3 years had actually cotested within the previous 5 years, which could bias the results.
Conclusions
Both barriers and self-efficacy to Pap testing scales demonstrated high internal consistency reliability, unidimensionality, and construct validity among Black women. These scales can be used by providers and interventionists to frame discussions around Pap testing. Further testing of these scales is necessary in larger samples and other Black subpopulations.
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