Recruitment
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RECRUITMENT
All participants are included via collaborating PCH organizations. The participant flow is displayed in Fig. Flow chart of the non-randomized controlled trialThe intervention group is recruited via two PCH organizations that both offer Shantala Infant Massage as a preventive intervention: Child and Family Centre Rijnmond (In Dutch: Centrum voor Jeugd en Gezin Rijnmond) in the city of Rotterdam and PCH Kennemerland (In Dutch: Jeugdgezondheidszorg Kennemerland) in Haarlem and surrounding (rural) areas. Parent–child dyads are eligible for participation in the study when they are about to engage in the Individual Shantala Infant Massage intervention, the infant is younger than 16 weeks and the parent is able to understand the study information and to complete the questionnaires in Dutch or English, with assistance if necessary. The parent taking part in the infant massage, is invited to participate in the study.Participants of the control group are recruited via the PCH organization in Amsterdam, which is part of the GGD Amsterdam. Recruitment is focused on 7 PCH locations within three specific areas of the Amsterdam region with relatively high rates of vulnerability in multiple domains. Inclusion criteria for parent–child dyads regarding the age of the infant and language understanding are similar as for the intervention group. The parent who spends most time with the infant is invited to participate in the study.For both the intervention and control group, suitable participants are notified of the study by PCH professionals. Contact information of interested parents is forwarded to the researchers with permission of the parents. Parents receive additional information on the research in a simple and accessible format. Participant information is provided in a written format, as well as in videos on a project website. To avoid desirable answers in the intervention group and to make participation more appealing for the control group, there is no emphasis on the effects of infant massage in the participant information. Instead, the focus of the study is described more generally, namely, the study is described as being about the wellbeing of infants and parents in the first 6 months and the support provided by PCH organizations during this period, including infant massage. Furthermore, parents are informed about the collection, storage, use and reuse of the data (note that in the Code of Conduct for Medical Research, ‘reuse’ is also referred to as ‘further use’), privacy regulations and rights under GDPR and contact information of the research team in case of complaints or questions.The parents are given time (a couple of days) to consider participation. Parents’ (digital) consent form precedes the pre-test questionnaire. In case the informed consent form and the questionnaire are not yet completed after some time, the researchers contact the parents via e-mail and/or phone to check if everything was clear and as a reminder. For the intervention group, it is important that the first questionnaire is completed before the start of the intervention. All parents who provide informed consent and complete the first questionnaire are enrolled in the study. After their study participation is completed, participants receive a gift voucher of 15 euros as a thank-you.