CHLAMYDIA TRACHOMATIS (CT) INFECTION is a leading cause of reproductive morbidity in women.1 Screening has been shown to reduce the prevalence of chlamydial infection in women and the incidence of pelvic inflammatory disease.2,3 Population-based screening is being debated in several countries, including The Netherlands. An important condition for large-scale screening programs is that the criteria of Wilson and Jungner are met.4 One of these criteria is acceptability of the program for the population screened.5 Besides technical aspects of the method used, this includes complex reactions to an often unexpected sexually transmitted infection (STI) diagnosis. In qualitative studies of the psychosocial impact of a CT diagnosis in women, three main themes were found: 1) a diagnosis of chlamydia was perceived as a stigma (feelings of guilt, unexpected results leading to stress); 2) the awareness of possible infertility despite early treatment; and 3) fear for the reaction of a partner.6
In this study, we first investigated the acceptability of screening in a population-based screening program in The Netherlands, which included invitation by the Municipal Health Service (MHS) home-based urine collection, outcome notification by mail, and referral of positive cases to regular healthcare services. Second, we assessed the experience of participants with the results and effects of screening. Third, the motivation for participation in future screening was studied.
Materials and Methods
The Chlamydia trachomatis Pilot Screening Study
In this study on screening of CT by home-based urine testing, four MHSs in The Netherlands invited 21,000 women and men aged 15 to 29 years. The participants received a package by mail containing an introductory letter, an information leaflet about chlamydia, a urine sampling kit with instructions, and a questionnaire. The coded (ID number) urine sample and questionnaire could be returned to the laboratory by mail and the MHS informed all participants of the result by mail. Chlamydia-positive participants received information about the infection, treatment, and partner notification, and were asked to consult the regular services. The participation rate was 41% (8,383); overall CT prevalence was 2%, as described elsewhere.7,8
Study Population and Questionnaire
To study the acceptability of the screening method, a comparative cross-sectional study was carried out among 156 CT-positives and a random sample of 600 CT-negatives (75 men and 75 women per MHS region). Information on sociodemographic characteristics (age, sex, education, self-chosen ethnicity, sexual behavior, symptoms, and history of STI) was collected through the questionnaire accompanying the initial screening offer.
Six to 12 weeks after receiving the result of their CT test, participants were invited to fill out a questionnaire with open questions, multiple-choice questions, or a five-point scale. The participants' opinion about the method of screening and their experiences with the procedure of urine collection and receipt of the result by mail were explored; for items, see Table 1. The motivation for participation and perceived consequences for partnerships was assessed in an open question asking for the reason for participation. The participants' feelings when receiving the result and their perception of disclosure of the result was assessed with items as described in Table 2. The experiences of infected persons with their healthcare workers were assessed. Participants were asked if they had discussed participation in the screening and the result with partner, family, friends, or colleagues. Infected participants were asked about the probable source. Actual experiences with disclosure of the result were scored. Awareness of possible infertility and fear of personal impaired fertility was asked for. The perceived importance of safe sex and intention of condom use with the current partner or with a new partner were assessed. Knowledge about chlamydia was evaluated. Perceptions of personal chlamydia screening, the wish for regular testing, and the preferred method were inquired.
Open questions were coded, and for validation reasons, 10% of the questionnaires were coded by a second person. The chi-squared test was used to compare proportions. For differences in means, a t test and variance analysis was performed. P values <0.05 were considered statistically significant. As a result of missing values, denominators are different. All items measured on a five-point scale were recoded, e.g., a negative feeling/disagreement would have a score of 1 and a positive feeling/agreement a score of 5. Analysis of reliability of the score was performed on items measuring the same concept and a sum score was computed when Cronbach's α was >0.70.9 The sum scores were divided by the number of items, resulting in scores from negative/disagree (1) to positive/agree (5).
Multiple logistic regression analyses were performed, with self-reported characteristics as independent variables and willingness to be tested in the future (vs. not wanting or not knowing) as the dependent variable. Only respondents who had been sexually active in the past were included in the regression analysis, because behavioral variables were available for this group only. The final model's ability to discriminate between participants according to their willingness to be tested in the future was quantified using the area under the receiver-operating characteristic curve.10 Statistical analysis was done with SPSS statistical software version 10.0 (SPSS, Inc., Chicago, IL).
The study population included 156 CT-positives and 600 CT-negatives. Eleven of these 756 persons were excluded from analysis because of sex/age differences with the original participant or returned mail because of unknown addressee. Overall response was 50% (374 of 745). As a result of missing ID numbers in 23 respondents, analysis could be done for 351 responders (including 14 male and 62 female infected persons), and 105 male and 170 female noninfected persons. Nonresponse analysis revealed only a significant difference by sex (male 38% vs. female 59%; P < 0.001).
Acceptability Screening Method
The invitation for the chlamydia test was well received by 84% (288) responders, 9% (32) felt neutral, 4% (12) experienced uncertainty, and 3% (10) felt annoyed about the screening offer. The majority of the participants highly appreciated the screening method and valued the possibility of collecting urine at home (Table 1). Internal reliability between these questions was good (Cronbach's α 0.71), resulting in an opinion score. The mean opinion score among infected participants was 4.05 (standard deviation [SD] 0.66) in men and 4.33 (SD 0.47) in women; among noninfected persons, 3.88 (SD 0.47) in men and 4.00 (SD 0.44) in women, a significant difference according to both sex (P <0.01) and result (P <0.001). A majority of 87% (266) thought it fine to receive the result by mail; 35% of these mentioned that access to additional information was satisfactory. Thirteen percent (44) thought the mailed result was difficult or too anonymous.
Experiences With Test Results of Chlamydia Screening
Surprise, stress, and anxiousness about health are reported mainly by chlamydia-positives and relief by -negatives. Remarkably, relief about the result was felt also by 15% positives (11, among whom 10 were women). Infected women more often than men reported a feeling of being dirty (30%  vs. 23% ; P = 0.04). Among CT-positives, 20% (14) were reassured; five of these took part because of own risk behavior. Of CT-negatives, 17% (44) were not reassured (Table 2). The feeling score (Cronbach's α 0.89) differed between CT-positives (mean 2.61; SD 0.66) and CT-negatives (mean 4.16; SD 0.40) (P <0.001). This indicates neutral feelings about the result in infected participants compared with positive feelings among noninfected participants. Among infected persons, 27% had no idea about the source of infection.
Sixty-three CT patients reported about their consultation with the healthcare worker. Most of them (67%) experienced the consultation as pleasant, 18% as neutral, and 16% as bothersome. During the consultation, 20% felt uneasy, 13% did not get their questions answered, 15% felt the healthcare worker was in a hurry, and 15% did not trust the healthcare worker. Compared with noninfected participants, CT-positives expressed their need to share the result more often, found talking about it difficult, and felt relieved after talking (Table 2).
Seventy percent of the participants thought their social environment would approve their testing for chlamydia. Sixty percent disclosed the result to family and friends, 92% to the current partner, and 72% to the expartner, independently of the test result. The experience with sharing the result was predominantly positive (75%) or neutral (22%). Fifty-one percent (81 of 162) of the noninfected reported that their partner was relieved. Forty percent of infected persons (19 of 48; all but one were women) expected a negative influence of the test result on their partnership. They reported feelings of guilt, anxiousness for the reaction of the partner, loss of trust, betrayal, and unfaithfulness. Six partners of infected participants (16%) were shocked about the result. However, the majority (92%) reported partners showing sympathy. Three women mentioned the end of the relationship, noting that it had been bad anyway.
Effects of Screening
Sixty percent of the infected persons self-reported an increase in knowledge after the screening compared with 40% of the noninfected (P <0.001). Questions regarding infecting others without having symptoms were answered correctly by 93% (326) and regarding infertility by 83% (286) participants. Approximately 50% of all men and noninfected women reported more awareness of possible infertility as a complication of chlamydial infection compared with 89% of infected women. Personal fears about own and/or partners' impaired fertility were reported more often by infected women than infected men (62% vs. 36%; P = 0.08). Infected participants expressed more often that safe sex was important for them than noninfected participants (84% of 76 vs. 39% of 267; P <0.001). There was only a minor difference in the reported intention to use a condom with a new partner between infected and noninfected (93% of 75 vs. 82% of 264; P = 0.06).
Motivation for Participation and Willingness to be Tested in the Future
A majority of 68% (224) took part in the screening program out of curiosity for their CT result; 25 of these 224 (12%) considered themselves at risk of having contracted CT. Actual infection was found in 17 of these 25 (68%). For 62 of the curious participants (28%), certainty about being not infected was decisive; eight of these were CT-positive, of which seven doubted the result.
Fifty percent (166) of the participants wanted to be tested regularly in the future, whereas 30% (103) did not want this and 21% (71) did not know. After adjustment in logistic regression analysis, current CT infection, younger age groups, multiple lifetime partners, short duration of or no partnership, and previous testing for chlamydia remained independent predictors for willingness to be tested in the future (Table 3). Interaction terms were not included, because they did not improve the model significantly. The Hosmer-Lemeshow goodness-of-fit test had a P value of 0.60, indicating adequate goodness of fit. The model discriminated well between participants willing to be tested and those who did not want to be tested or were not sure (area under the curve 0.82 [95% confidence interval 0.77–0.87]). Of those who wanted to be tested regularly, 82% (134) would like to be invited by the MHS for screening, 12% (19) would take care of their testing themselves, and 6% (13) wanted to visit or be invited by their general practitioner (GP). Participants especially mentioned the importance of the low threshold for getting test materials.
Acceptability Screening Method
The unsolicited STI test offer by the MHS as well as the method of screening by urine collection at home was generally well accepted. It was appreciated to have easy access to testing and to collect urine at home in privacy at a convenient time like described before.11 In previous studies, the home-based screening method was also shown to be well-accepted.12–14 In The Netherlands, the public is familiar with the MHS and our participation rate was comparable with the study in Amsterdam where the invitation was sent by the GP.15 In The Netherlands, STI test results are usually communicated personally, and not having a face-to-face discussion about a positive result could be a disadvantage.16 Receiving the STI result by mail was perceived as acceptable, provided that questions concerning the result could be answered.
Experiences With Test Results of Chlamydia Screening
It is to be expected that infected participants experience their result less positive than those who are not infected do. Twenty percent of those infected, however, expressed reassurance, indicating that now something could be done about their infection. The paradox is that damage may well be present at diagnosis and that treatment cannot always reverse this. A noninfected person with high-risk behavior may unjustly feel reassured by the absence of a chlamydia infection. The importance of taking up or continuing safe sex behavior should be emphasized. Having an STI might evoke distress, self-disgust, and worry, as was described previously.6,17 The fear of stigma after diagnosis of an STI could be a barrier to testing.18 Fortunately, a considerable number of the infected persons did not report these feelings. The need of supporting counseling is obvious, especially because this concerns unexpected STI results.
Although the majority of the consultations at the GP or a sexually transmitted disease (STD) clinic were experienced as pleasant, some participants felt annoyed. A feeling of uneasiness might reflect their own uncertainty about the diagnosis, but apparently not all healthcare workers were able to make their patients feel comfortable and gain their trust. This is a serious signal and continuous training in STI counseling as part of screening activities is necessary. Openness is a prerequisite for partner notification and the need for training of GPs has been emphasized before.19–21
It is encouraging that a majority of the participants discussed STI testing and results in their social environment and experienced supportive reactions. Nevertheless, those who were infected were confronted with negative reactions more often. This underlines the importance of health education to reduce a stigma of having an STI.11,22
Effects of Screening
Infected persons, and particularly women, often have negative expectations about the reaction of their partners. The positive reactions of partners of both noninfected and infected are encouraging, but suspicion and fear for infection in partners of positives deserve attention.
Potential infertility is a concern for both women and men, and understandably more so for infected women. The asymptomatic nature of the infection creates uncertainty about the duration of infection. An assumed long duration may lessen fears about a partners' infidelity, but could also increase anxiety about possible reproductive morbidity.6 These issues should be addressed explicitly during counseling.
Besides some critical issues regarding screening, we have also observed positive effects of this screening program: increase of knowledge and awareness about condom use. Infected participants reported more often the intention to use condoms. Knowledge and intention are a prerequisite for behavioral change, yet not sufficient.23 The question of whether participants would indeed engage in more safe behavior is beyond the scope of our study.
Motivation for Participation and Willingness to be Tested in the Future
We motivated people to participate by emphasizing the possibility of treatment in case of infection. In our study, the majority indeed took part to know their result, but only a minority of those perceived themselves to be at risk. Seeking certainty of not being infected was decisive to participate in more than one fourth of the participants, and those who turned out to be infected doubted the result. This suggests that risk perception is not adequate. This is exemplified by the fact that 27% had no idea where their infection was acquired.
Because we have performed a single screening round, the crucial question is whether participants would be willing to be tested repeatedly. Among the participants, 50% wanted to be tested regularly in the future, the readiness is higher in persons who can be regarded having an elevated risk for CT infection. Unsurprisingly, persons who just found out to be infected are more motivated to be tested regularly. We also showed that a history of earlier testing is an indicator for willingness to be tested in the future, independent of the STI result. Persons without a current or with short-term relationships, or with multiple lifetime partners were more likely willing to be tested. It is encouraging that the two younger age groups are motivated for testing. For persons in long-term monogamous relationships, there is not a great need for chlamydia testing. It remains to be seen whether the nonresponders of our study would show the same level of willingness to be retested.
The majority of the participants who wanted to be screened regularly preferred to be invited by the MHS, underlining the acceptance of our screening method. It also emerged clearly from our data that a very low threshold for getting test material is a prerequisite for testing.16,18 A matter of concern is the lower response in men. Shared responsibility in stopping transmission between partners requires testing of men and women.
Limitations of Our Study
A limitation of our data is that this study includes only participants of the CT pilot study and the response rate was 50%. There might be a selection bias toward motivated participants with favorable opinion, because they took part both in the original screening and in the acceptability study. Unfortunately, it was not feasible to approach nonresponders of the PILOT CT Study for this study. Among the participants of the PILOT CT Study, non-Dutch persons were underrepresented, and possibly a different approach is needed to motivate them.8
In conclusion, screening for CT by the MHS through urine collection at home, outcome notification by mail, and treatment by regular health services is well-accepted by the target population of 15- to 29-year-old women and men. The method can be used in future screening of the general population, as well as for selective screening of high-risk groups. Access to personal counseling is essential, with focus on unintended effects of positive results, especially in women. Training of healthcare workers in STI counseling should be strengthened. Motivation of men to get tested deserves special attention. Participants with a high risk for chlamydia infection were willing to be tested regularly. Interventions for stimulating active testing among non-Dutch high-risk groups combined with methods to increase risk perception should be developed.
H.G. wrote the first draft and finalized the paper. All members of the CT Pilot Group (H.G., J.v.B., I.V., J.B., C.H., J.R., A.C., F.d.G., D.v.S., M.V.) and O.d.Z. have contributed to the study design and protocol, collected and interpreted data, critically reviewed the draft, and were all involved in the final report. Statistical analysis was performed by H.G. in collaboration with I.V.
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