2.1. Study Design and Setting
A cluster-randomised longitudinal three-armed trial is proposed. The initial randomisation process has been performed via computer-generation, to allocate the 14 regional districts of the AOK Baden-Wuerttemberg, in Southwest Germany, to one of three study arms. Participants in the first study arm will receive an on-site counselling intervention, study arm two will receive an online counselling intervention, while those in study arm three comprise a waiting-list control group. Participants in the control group will be able to receive the consultation after data collection. The newly developed counselling intervention will address the relationship between LRRFs and pregnancy, covering information on nutrition, physical activity, relaxation, stress management, and substance use during pregnancy. This study will be accompanied by a process evaluation; further details are provided in the related sections. For the development of the study protocol, the standard protocol items of the recommendations for interventional trails (SPIRIT) (12) were used. Possible changes to the procedure will be communicated to all relevant groups such as investigators, funder, study registry and AOK Baden-Wuerttemberg employees.
2.2. Study Population and Counsellors
The target group will include pregnant women and women of childbearing age who are between 18 and 49 years, able to give consent and insured with AOK Baden-Wuerttemberg. The ability to read and understand German is a requirement for participation.
The study counsellors will be AOK Baden-Wuerttemberg employees who have completed a degree in nutrition or sports science and have experience with LRRF counselling. They will complete a standardised training in advance.
2.3. Recruitment of Study Participants
Participants are made aware of the study with the help of flyers in waiting rooms of gynaecological practices. In addition, further advertisements will be placed via health insurance company advertising channels (e.g. social media and insurance magazines). Interested participants can then contact AOK Baden-Wuerttemberg by phone. After participating in the study, all participants will receive an incentive. The incentive is a voucher code for the e-book “Handbook of Family Health” (13) with a value of EUR 12,99.
2.4. Randomization Process
The 14 district directorates of AOK Baden-Wuerttemberg (Fig. 1) are randomly assigned to one of the three study groups: the on-site intervention group, the online intervention group, or the control group. The cluster randomization will be conducted by an independent operator using the statistical program R (Version 1.3.5) with the randomizr package. Similarly, the counsellors will be allocated according to their place of employment.
Figure 1. AOK Baden-Wuerttemberg district directorates.
2.5. Assignment of Interventions
Those interested in the study will be invited to contact AOK Baden-Wuerttemberg by phone to receive information on participation in the study from a trained staff member. Participants will be randomly assigned to one of the three study groups within their district of residence.
2.6. Interventions
The interventions are educational, aiming to increase the awareness of LRRFs during pregnancy and the concomitant healthy behaviours supporting women. To achieve this, the interventions address LRRFs related to nutrition, physical activity, relaxation, stress management, and substance use for a planned period of six months. The SPIRIT (12) and TIDieR checklist (14) were used for the preparation of the intervention (see the Supplementary Materials). Table 1 shows the SPIRIT figure.
Table 1
Enrolment, intervention and assessments of the "AOK-Family+"
| STUDY PERIOD |
| Enrolment | Allocation | Post-allocation |
TIMEPOINT | -t0 | -t0 | t0 | t1 | t2 |
ENROLMENT: | | | | | |
Eligibility screen | X | | | | |
Informed consent | X | | | | |
Allocation (cluster randomization) | | X | | | |
INTERVENTIONS: | | | | | |
on-site health counselling | | | | X | |
online health counselling | | | | X | |
Waiting control group (does not receive counselling intervention) | | | | | |
ASSESSMENTS: | | | | | |
health behaviour | | | X | | X |
health knowledge | | | X | X | X |
customer satisfaction and usability | | | | X | X |
2.6.1. The Three Study Arms
The three study arms are outlined in this section. Participants receiving the on-site intervention (arm one) will receive counselling for 45 minutes at a local health centre. The counsellors will use an information brochure on the impact of LRRFs during pregnancy and a conversation guide to support the process. Following this, the participants will be given the information brochure to take home.
In the online intervention (arm two), participants will engage with a 45-minute online counselling session via a screensharing system with a video facility. The counsellors will share a digital PDF containing important information about the impact of LRRFs during pregnancy. The counselling process will also be supported by short videos of expert interviews (approx. one minute per video), where relevant experts will provide information on the topics of nutrition, physical activity, relaxation, stress management, and substance use. Counsellors will receive a conversation guide to structure the counselling, and the participants will receive their information brochures via postal mail following the session.
Participants in the waiting-list control (arm three) will not receive counselling during the intervention period. However, at 6 weeks post-intervention, and after completing the t2-questionnaire, they will be invited to participate in online or on-site counselling and/or to receive the information brochure via mail.
All participants will have the option to terminate their participation in the study via a digital form on the AOK Baden-Wuerttemberg website. Table 2 summarises the three interventions.
Table 2
A summary of the three interventions of the study and the corresponding resource materials employed.
On-Site Intervention, study arm 1 | Online Intervention, study arm 2 | Waiting-list Control, study arm 3 |
45-minute on-site counselling at health centres covering the impact of LRRFs during pregnancy Materials • Information brochure provided for participants • Conversation guidelines provided for the counsellors | 45-minute online counselling covering the impact of LRRFs during pregnancy Materials • Interactive PDF shown via screen-sharing • Expert and explanatory videos • Information brochure mailed to participants • Conversation guidelines provided for the counsellors | No consultation about LRRFs. Optional online or on-site consultation following full data collection (t2); the information brochure can be requested separately. |
2.6.2. Content of the Counselling Resources
Content of used resources for supporting participants and counsellors is based on the current scientific recommendations for nutrition, physical activity, relaxation, stress management, and substance use during pregnancy. This content was compiled from the guidelines published by relevant institutions and professional societies (15–17) and the current research evidence regarding LRRFs during pregnancy. These study resources were subsequently discussed and summarised by researchers at the Heidelberg University Hospital, Germany, and then prepared for inclusion in the counselling sessions. Several experts further reviewed and modified the content as necessary. This process is intended to ensure content consistency in all subject areas pertaining to the study and provides a valid platform for comparison of the three study groups. The design and finalisation of the resource materials were performed in collaboration with service providers associated with AOK Baden-Wuerttemberg.
2.6.3. Training for Counsellors
Study counsellors must independently complete a four-hour e-learning module detailing the context and application of information on the study design and procedure, and the relevant scientific information on the relationship between LRRFs and pregnancy. The successful completion of the e-learning module requires an 80% minimum test score in a following multiple-choice assessment. Approximately 50 counsellors are expected to participate in the training. The e-learning module was developed by an external service provider associated with AOK Baden-Wuerttemberg.
Where medical questions and topics surpass the expertise and competencies of the counsellors, participants will be referred to the relevant care-pathway.
2.7. Monitoring of the Intervention Process
Researchers from Heidelberg University Hospital will be available for consultation with the counsellors throughout the intervention period. In order to ascertain if the planned process will work as part of the counsellor’s daily routine, feedback will be sought from the counsellors after the initial health education sessions. If problems arise, the process, or the procedures, will be adjusted accordingly.
2.8. Study Outcomes
2.8.1. Primary Outcomes
The primary outcomes of this study are expected to be improved knowledge, and accompanying healthy behaviours, relating to LRRFs during pregnancy.
Health Knowledge
Participants’ knowledge related to LRRFs during pregnancy will be measured by a questionnaire developed by Oechsle et al. (8). This questionnaire was developed to assess knowledge and attitudes of pregnant women concerning alcohol consumption, smoking, nutrition, physical activity, oral health, and medication. The questionnaire has been modified and piloted for the AOK-Family + study. In this process, an additional option (uncertain) was added to the previously dichotomous answer options (yes/no), and the individual wording of questions was adjusted. In addition, questions about oral health were replaced with questions about relaxation behaviours.
Health-Related Behaviours
Health-related behaviours will be assessed concerning nutrition, physical activity, relaxation and stress management, and substance use. As no all-encompassing instruments exist for this specific purpose, existing instruments for measuring health-related behaviours with regard to nutrition, physical activity, relaxation, stress management, and substance use were tested; those deemed suitable were adopted with a few adjustments according to the needs of the study. The final survey instrument is based on the AUDIT-C questionnaire, which is used to measure alcohol consumption (18, 19), and the questionnaire from the study “German Health Update” (GEDA 2014/2015) by the Robert Koch Institute (20). These parts relate to the assessment of physical activity (European Health Interview survey—Physical Activity Questionnaire (EHIS-PAQ)) (21) and tobacco use (20). The Stress and Coping Inventory (SCI) (22) will be used to measure active stress management.
2.8.2. Secondary Outcomes
Client Satisfaction and User-Friendliness
The secondary outcomes include client satisfaction, practicability and user-friendliness of the consultations. These will be evaluated using existing internal (not published) standard questions from AOK Baden-Wuerttemberg regarding customer satisfaction. The topics included are satisfaction with the enrolment process, satisfaction with the counsellor’s engagement, satisfaction with the counselling itself, possible recommendations for the counselling, and the subjectively perceived benefit of the counselling. These questions will only be addressed to the intervention groups (study arm one and two).
2.8.3. Other Measures
All participants will be asked questions to determine their socio-demographic status. These include age, education, occupation, country of birth, parents’ countries of birth, and household income.
2.9. Participant Timeline, Data Collection, and Management
Following verbal informed consent, a consultation appointment will be arranged for the intervention groups, and the participants will receive access (QR-Code and URL) to the first online questionnaire (t0), which will also be posted by mail. Before starting the questionnaire, the consent of the participants is obtained again. This baseline questionnaire should be answered up to 24 hours before the counselling session (duration approximately 20–30 minutes) and will capture their socio-demographic data, health knowledge, and health-related behaviours. At the appointment, before the start of the counselling session, the participants will be asked whether the baseline questionnaire (t0) has already been completed. If not, completion of the questionnaire will be requested prior to counselling. Otherwise, the counselling intervention (on-site/digital) will take place and will last for approximately 45 minutes. Immediately after counselling, the counsellors will provide participants with access (QR-Code and URL) to the second online questionnaire (t1) to measure the short-term effect of the counselling on health knowledge, together with information regarding client satisfaction and the user-friendliness of the counselling (secondary outcomes) (duration 10 min). This questionnaire should be completed directly after counselling at the health centres or after leaving the digital room.
To measure longer-term effects of the counselling, a follow-up questionnaire six weeks after t0 will be conducted, including participants’ health knowledge and healthy behaviours (t2), as well as their perceived user-friendliness and client satisfaction (duration approximately 30–35 minutes). The participants will receive access (QR-Code and URL) to the last online questionnaire by mail.
The waiting-list control group will receive access (QR-Code and URL) to the baseline questionnaire after the gave consent for study participation and receive the last questionnaire (t2) six weeks later by mail. After completion of the follow-up survey, the participants in the control group can individually arrange a requested AOK-Family + consultation.
All data will be collected anonymously using the online survey system LimeSurvey. The digital questionnaires can be filled out on personal smartphones or personal computers. Personal data, for identification as an AOK Baden-Wuerttemberg insured client, will be managed by AOK Baden-Wuerttemberg in accordance with their data protection standards. The Department of General Practice and Health Service Research (University Hospital Heidelberg) will only receive anonymous data from the questionnaires. The storage of this data occurs on a computer that is at least externally 2-fold encrypted and is protected against unauthorised access. Only researchers at Heidelberg University Hospital involved in the study have access to this data. A code created by the participants themselves at the beginning of each questionnaire enables the questionnaires from the different survey periods to be assigned accordingly. This code has five digits and is determined by four questions on invariable characteristics of the participants. Anonymity is preserved as the code remains exclusively with Heidelberg University Hospital and thus does not allow the person to be identified.
In order to generate robust data sets, the intervention will only start after the baseline questionnaire (t0) has been completed, and the second questionnaire will be directly administered during the appointment (t1). To reduce the drop-out rate for the six-week follow-up, participants will receive a reminder after 7 weeks and the incentive only after full participation. Figure 2 illustrates the study design and process.
Figure 2. The study design with data collection and participant timelines.
2.10. Sample Size Calculation
The power calculation was performed assuming a probability of successful participation by 50% of participants in the control group, and a perceived relevant improvement of the successful participation by 65% of participants in the intervention groups. These assumptions were based on the results of a cross-sectional study by Oechsle et al. (8) on the health knowledge of pregnant women regarding LRRFs, in which knowledge gaps and their health effects were identified, and on studies indicating the need for improvement in the health behaviours of pregnant women (5–7, 23).
Furthermore, sample size calculations were based on a power of (1 − ß) = 80% and a significance level of α = 5% (two-sided). To account for the cluster structure, with participants nested within customer and service centres, a small intra-cluster correlation coefficient (ICC) of 0.01 was assumed. As there are 14 district directorates of AOK Baden-Wuerttemberg (arm one = 4, arm two = 5, arm three = 5), it is estimated that there would be approximately 36 participants per cluster. Based on these assumptions and the perceived relevant difference of 50% in the control versus 65% in the intervention group, the sample size per study arm will be n = 168. This implies a total sample size of n = 504. A dropout rate of 20% is assumed; therefore, n = 638 participants must be enrolled in the study at time t0 to reach n = 504 for analysis.
The above calculations were performed using R (Version 1.3.5) and the sjstats package (Version 0.18.1).
2.11. Statistical Analysis
Descriptive analyses will be conducted to determine the study population characteristics and the differences in the primary and secondary outcomes between the study arms. The primary analyses will be intention-to-treat analyses. If insufficient data are available, a multiple-imputation procedure will be considered to impute the missing values. The results of the analysis will be publicised to all relevant groups through publications and reports.
2.11.1. Primary Outcomes
To test the effect of the intervention on the primary outcomes (health behaviours and health knowledge) at t2, both intervention arms will be compared to the control arm as adjusted for baseline values (t0) using multivariate regression analysis. This method offers the option to control for potential baseline differences between study arms.
2.11.2. Secondary Outcomes
Client satisfaction with and the user-friendliness of the consultations will be analysed accordingly without, however, controlling for baseline values, as these questions are directly related to the intervention and will only be asked in the intervention groups at t1 and t2. Possible associations with potential improvements in health knowledge and health behaviours will also be analysed using multivariate regression analysis. In addition, an exploratory analysis to determine which materials influence the effectiveness of the intervention and whether these differ according to the form of counselling (on-site/online) will be conducted.
2.11.3. Other Exploratory Analysis
To further analyse which participants experienced behavioural and knowledge changes after the intervention, exploratory analysis will be performed. This analysis will investigate what factors influence behavioural and knowledge change, e.g., socioeconomic parameters (education, income, occupational status, and socioeconomic status), the number of previous pregnancies, the number of biological children, and previous counselling regarding LRRFs.