Non-participation in chlamydia screening in The Netherlands: determinants associated with young people's intention to participate in chlamydia screening

Abstract

Background: In The Netherlands, a national chlamydia screening program started in 2008, but the participation was low and the screening was not cost-effective. This study aimed to explore unconscious and conscious associations with chlamydia screening (16-29 year-olds). In addition, we examined whether information presented in chlamydia screening invitation letters had an effect on the evaluation of these determinants compared to a no-letter group.

Methods: An Internet survey was conducted that included self-report measures of attitude, susceptibility, severity, unrealistic optimism, subjective, moral, and descriptive norm, perceived behavioral control, outcome expectations, barriers, intention, and a response time measure to assess unconscious associations of chlamydia screening with annoyance, threat and reassurance.

Results: On the unconscious level, participants (N = 713) who received no information letter associated testing for chlamydia with annoyance and threat, but also with reassurance (all p's < .001). On the self-report measures, participants showed a low intention towards chlamydia screening (M = 1.42, range 1-5). Subjective norm, moral norm, perceived susceptibility and attitude were the most important predictors of the intention to screen (R2 = .56). Participants who rated their susceptibility as high also reported more risky behaviors (p < .001).In the groups that received a letter (N = 735), a weaker unconscious association of chlamydia screening with annoyance was found compared with the no-letter group (p < .001), but no differences were found in reassurance or threat. Furthermore, the letters caused a higher intention (p < .001), but intention remained low (M = 1.74). On a conscious level, giving information caused a more positive attitude, higher susceptibility, a higher subjective and moral norm, and more positive outcome expectations (all p's < .001).

Conclusion: Subjective norm, moral norm, susceptibility, and attitude towards chlamydia might be crucial targets to increase chlamydia screening behavior among sexually active young people. This study shows that informational invitation letters increase the intention and the intention-predicting variables. More evidence is needed on whether screening behavior can be increased by the use of an alternative information letter adapted to the specific unconscious and conscious determinants revealed in this study, or that we need other, more interactive behavior change methods.

Figure 1

The Single Category Implicit Associations’ Test (SC-IAT). Single Category Implicit Association tests (SC-IATs) are computerized sorting tasks in which, based on reaction times, impulsive preferences are measured. Very simplified in the Figure 1 (three times a computer screen with a keyboard – the ‘E’ and ‘I’-button emphasized), the procedure of a SC-IAT is displayed. The SC-IAT consists of a practice block, and two trial blocks. In a first practice block, participants learn to respond to attribute words (appearing in the center of the computer screen) which have to be categorized in two categories. In this example the attribute categories are ‘neutral’ and ‘annoying’, and are positioned on the left and right side at the top of a computer screen. The attribute words (see Table 1) that appear one by one in the center of the computer screen have to be classified to the attribute categories with either the left (E) or right (I) response key. Participants are to assign the word as fast and accurate as possible to the correct category by pressing the appropriate response key. The assignment of the left key (E) and right key (I) are balanced across participants. The attribute words can be neutral, negative or positive; in this study: annoying, reassuring, and threatening. In the two following blocks, people continue categorizing attribute words, but now the label category ‘Chlamydia screening’ is added to either one of the categories. In block 2, ‘Chlamydia screening’ is combined with ‘neutral’, while in block 3 ‘Chlamydia screening’ is combined with ‘annoying’ and vice versa. If, for example, there is a significant higher mean sorting reaction time when ‘Chlamydia Screening’ is combined with ‘Annoying’ compared to when it is combined with ‘Neutral’, respondents have an impulsive negative reactance towards Chlamydia screening; they associate Chlamydia screening more with the attribute annoying than with a neutral attribute.

Figure 2

Flowchart illustrating the procedure of the study and the number of participants.