Study design
To answer the research questions, a quasi-experiment will be performed in which respondents from an ongoing prospective study on the mental health and quality of life of maltreated children after a report to an AMK [35] will be asked to complete an additional questionnaire at follow-up assessments. The quasi-experiment will consist of two post-intervention assessments of two nonequivalent groups (intervention group and control group) (see Figure 1). The study sample of the prospective study consists of maltreated children and their primary caretaker. These parent–child dyads were recruited for participation in the prospective study during the AMK investigation following a report to an AMK. Based on information from AMK records, the study sample will be divided into two groups: an intervention group, in which the Child-Interview intervention was used during the AMK investigation, and a control group, in which the intervention was not used (adult-only intervention).
The gold standard for experimental and effectiveness and cost-effectiveness studies is a randomized controlled trial (RCT), in which participants are divided to two study groups based on random assignment. The Dutch Medical Ethics Committee for Mental Health Care (METiGG) did not approve of a RCT, because randomization might result in a parent–child dyad receiving a suboptimal approach (in this case the adult-only intervention), which the committee decided was not ethically acceptable in the case of vulnerable young children. Although evidence on the adult-only intervention is lacking, this is supported by Article 33 of the Declaration of Helsinki. This article states that it is not acceptable to withhold treatment/intervention when it is known that this treatment can be lifesaving or that abstinence might lead to irrecoverable damage to the subject [36].
While preparing for the study, however, we found from AMK records that although the Child-Interview intervention is the preferred method according to the AMK manual [13], the Child-Interview intervention was not used during the investigation in a substantial number of AMK investigations. This enabled us to propose a quasi-experimental design in which an existing study sample (from the prospective study mentioned above) was divided into two groups based on the intervention they had received during the AMK investigation. Data collection for the quasi-experiment could be incorporated in this prospective study (see Figure 1). This design would make it possible to answer the research questions without randomization, though a disadvantage of this design is the possibility of selection bias. The economic evaluation will involve a combination of a cost-effectiveness analysis (CEA) and a cost-utility analysis (CUA).
Assessment
This study will consist of two assessments: A and B (see Figure 1). Assessment A will take place at the same time as assessment 2 of the prospective study (6 months after the AMK investigation). Assessment B will take place six months later, at the same time as assessment 3 of the prospective study (12 months after the AMK investigation).
At assessments A and B, children and parents will be asked to complete a questionnaire. A member of the research team will meet the parent and child at a place of their choice (in most cases their own home) to assist them. The way in which the questionnaire is to be completed will be discussed with the parent and the child, and will depend on the participants’ reading and writing skills. If reading and writing skills are poor, a research team member will read out the questions and write down the participant’s answer on the questionnaire form. If reading and writing skills are sufficient, participants may choose to complete the questionnaire by themselves. To prevent the parents from influencing the children’s answers, parents and children will be requested to complete their questionnaires in separate rooms. Respondents will be rewarded for their participation by a 10 euro gift voucher for the parents, while the children will receive either a 5 euro gift voucher (children > 10) or an age-appropriate present (6–10 years).
Target population
The target population will consist of maltreated children aged between 6 and 18 years and their primary caretaker. Inclusion criteria are (1) a report to an AMK about physical and/or emotional abuse, physical and/or emotional neglect and/or sexual abuse, (2) one child per family. When a report relates to more than one child of the same family, the oldest child within the age range will be included, (3) sufficient verbal and cognitive capacities of both parent and child, as the study will use mainly self-report methods for data collection, and (4) no intention to leave the Netherlands within the next 6 months, in view of the follow-up period.
Sample size and recruitment
Participants from an ongoing prospective study on the mental health and quality of life of maltreated children after a report to an AMK [35] will be contacted to complete assessments A and B (see Figure 1). Parents and children will be asked to give written informed consent for their participation. Five dyads from the sample of this prospective study were excluded because they did not meet age criteria, while for 22 parent–child dyads maltreatment was not verified during the AMK investigation and for 17 dyads the type of maltreatment did not meet inclusion criteria of the quasi-experiment. Hence, the study sample for the present quasi-experiment will include 117 parent–child dyads. A sample size calculation confirmed that this is a sufficient number of participants. Based on the ability to detect a medium effect size or larger clinical effect (Cohen’s d > 0.45) [37] and tested at a conventional power of (1-beta) 0.80 and alpha of 0.05 (one-tailed testing), a total number of 110 parent–child dyads is required.
Supported by AMK records, this sample will be split up into two groups: an intervention group, in which the Child-Interview intervention was used during the AMK investigation, and a control group, in which the intervention was not used (adult-only intervention).
Child-interview intervention vs. adult-only intervention in AMK investigation
All reports to an AMK are discussed in a multidisciplinary team meeting which draws up a plan for the investigation. It is at this team meeting that the choice of AMK investigation with or without the Child-Interview intervention is made, based on information from the person who reported the alleged maltreatment.
AMK investigation without child-interview intervention
If the multidisciplinary team decides on AMK investigation without the intervention, only adults will be approached for information. The multidisciplinary team will decide which adults should be approached. Usually, the parents, teacher(s) and family doctor are part of this investigation, but other adults such as family members, social workers, therapists, or healthcare specialists can also be approached, depending on the social environment of the reported child/family. Information will be collected by phone, email contact or by a home visit.
AMK investigation including the child-interview intervention
In addition to information from adults (see above), the child and his/her siblings will be asked as informants. The Child-Interview intervention comprises the child being interviewed by an AMK employee. This interview takes place at the child’s home or at school, in a separate room. The duration of the interview depends on the child’s needs. The aim of the interview is for the AMK employee to discover if there are problems in the family or its surroundings, if the child needs care and what type of care would be suitable. An additional aim is to increase the child’s sense of being in control.
The Child-interview intervention used by the AMKs is part of the investigation to substantiate a report of suspected child maltreatment and to identify the needs for child and family care. It does not serve a forensic purpose.
Outcome measures
(1) Effectiveness study
Mental health
Children’s mental health (in terms of internalizing and externalizing psychological problems) as observed by the parents, will be measured with the Dutch version of the Child Behavior Checklist (CBCL) [38]. Parents will be asked to what extent they observe various behavioral and emotional problems in their child. The CBCL uses a 3-point scale and consists of 113 items. Internal consistency is good (α .97) [38].
Quality of life
Children’s quality of life will be measured with one of three age-appropriate versions (5–7, 8–11, 12–18 years) of the Dutch translation of the Pediatric Quality of Life Inventory (PedsQL) [39]. Children will be asked to express their concerns on the dimensions of physical health and psychosocial health, the latter consisting of the subdimensions of emotional functioning, social functioning and school functioning. The overall quality of life score will be obtained by adding up the scores on all dimensions. The PedsQL uses a 5-point scale (or a 3-point scale for the 5–7 version) and consists of 23 items. Internal consistency is good (α .82- .85) [39].
(2) Economic evaluation study
Societal costs
Healthcare costs of the child and the family will be measured using an adapted version of the Trimbos Institute Medical Technology Assessment Cost Questionnaire for Psychiatry (TiC-P) [40]. This questionnaire will be completed by the parent. As the TiC-P is not completely suitable for this intervention, the TiC-P had to be adapted, using a bottom-up approach. In this procedure, AMK managers and AMK workers were asked to review the TiC-P for the purpose of studying a maltreated population and they were asked to add services that families that are reported to an AMK use regularly and that were missing from the TiC-P. This resulted in a suitable questionnaire to record societal costs of maltreated children and their families. The updated version of the TiC-P questionnaire included the following services: general practitioner, company doctor, first aid post at hospital, medical specialist at hospital, hospitalization (including general hospital, psychiatric hospital, rehabilitation center, university hospital), psychiatrist/psychologist/psychotherapist working at hospital, psychiatrist/psychologist/psychotherapist with private practice, physical therapist, alternative healer (e.g. homeopathy), self-help group therapy, child welfare service on outpatient basis, child welfare service as day care, child welfare service on inpatient basis, AMK, youth and family center, infant welfare center, regional public health service, home care, personal care budget (allocated by local government), social worker, school (including school doctor, compulsory education officer), police, probation service, addiction service, financial assistance, and lawyer/legal aid.
Costs will be valued on the basis of guideline prices derived from the updated Dutch manual for cost analysis in healthcare research [41]. As the guideline only includes healthcare costs, costs outside the healthcare sector will be valued separately.
Quality adjusted life years (QALYs)
An increased quality of life is expressed as a utility value on a scale from 0 (death) to 1 (perfect quality of life). In health economics, utilities are combined with survival estimates and aggregated across individuals to generate quality adjusted life years (QALYs). A one-year increase in the duration of life (without change in quality of life), or an increase in quality of life from 0.5 to 0.7 utility units for five years, would both result in a gain of one QALY. Children’s QALYs will be derived from a thermometer question. Children will be asked to answer the question: “On a scale from 1 to 10, how healthy did you feel over the past 6 months?” The scores will be converted to utility scores by dividing by 10, obtaining a score between 0.00 and 1.00. The change in utility value between the two assessment points will be multiplied by the duration of the intervention effect to obtain the number of QALYs gained.
Analyses
Data will be analyzed according to the intention-to-treat principle. The similarity of baseline characteristics (socio-demographic characteristics, costs and outcomes) between the two AMK investigation interventions will be examined using univariate tests and Chi-square tests. Loss-to-follow up will be accounted for by imputing missing data using regression imputation.
(1) Effectiveness study
A multivariate regression analysis will be performed in which outcomes of mental health and quality of life will be compared between the Child-Interview intervention group and the control group (adult-only intervention). This will be done at follow-up (assessment B), 6 months after assessment A and a year after the intervention. Covariates will be taken into account.
(2) Economic evaluation study
In this study, additional costs and additional outcomes of the Child-Interview intervention will be compared with those of the adult-only intervention. The incremental cost-effectiveness ratio (ICER) will be expressed as the incremental costs per degree of improvement in mental health of the Child-Interview intervention group in comparison with the control group (adult-only intervention). The incremental cost-utility ratio (ICUR) will be expressed as the incremental costs per QALY of the Child-Interview intervention group in comparison with the control group (adult-only intervention).
The ICER (and ICUR) will be calculated using ICER = (Ci-Cc)/(Ei-Ec), where Ci is the annual total costs of the Child-Interview intervention, Cc the annual costs of the adults-only intervention, Ei the effect at 6-months follow-up for the Child-Interview intervention and Ec the effect at 6-months follow-up of the adult-only intervention. The robustness of the ICER will be checked by non-parametric bootstrapping (1000 times). The bootstrap replications will be used to calculate 95% confidence intervals around the costs. The bootstrapped ratios (ICER and ICUR) will be graphically presented in two ways: (1) plotted in a cost-effectiveness plane, in which the vertical line reflects the difference in costs and the horizontal line reflects the difference in effects, and (2) in a cost-effectiveness acceptability curve, showing the probability that the Child-Interview intervention is cost-effective based on a range of ceiling ratios (the maximum amount of money society is willing to pay to gain one extra unit of effect or a gain in QALY). Additionally, the robustness of the base-case findings will be assessed using a sensitivity analysis [42]. This economic evaluation will be performed from a societal perspective. Bootstrapping will be carried out in Excel.
Collaboration
This study is a joint project of Trimbos institute, the Netherlands Institute for Mental Health and Addiction (Utrecht), the CAPHRI School for Public Health and Primary Care, Maastricht University and VU University Amsterdam. The research is funded by the Netherlands Organisation for Health Research and Development (ZonMw) (project No. 15700.2012) and is registered in the Netherlands Trial Register, part of the Dutch Cochrane Centre (NTR3728). This study was approved by the Dutch Medical Ethics Committee for Mental Health Care (METiGG) in February 2012 (NL31267.097.10).