Selective mutism - A follow up study

SM is a relatively rare psychiatric disorder in which a child consistently
fails to speak in specific situations. Following a considerable number of
single case studies, several cohort studies have been published in the last
years. Despite these recent efforts, systematic evaluation of long term
diagnosis and outcome in large patient samples is missing. Consequently many
issues about the etiology of SM, mediating factors and prognosis remained
unsolved.
In the department of child and adolescent psychiatry, UMC Utrecht, two
behavioural therapists became specifically interested and experienced in the
treatment of SM, resulting in a relatively large number of referrals, compared
to other institutions. A sample of approximately 100 children with this
relatively rare disorder has been collected. This is one of the largest samples
in the world especially when it concerns samples that were used in follow-up
studies.

The goal of the present study is to describe this unique sample on the basis of
dossier analysis at the time of referral and reassess all individuals for
follow up.

VERPLAATST: The main objective of this study is to assess long-term outcome of
subjects once referred to our department with SM.

The main questions are: what rest-pathology might be found in individuals once
treated for SM and which factors might have influenced outcome? Are there
subgroups within the sample reflecting different aetiologies and do different
subgroups have different prognoses? Do children with SM show underlying
neuropsychological deficits that might have played a role in the occurrence and
persistence of their symptoms? To which extend are pervasive developmental
disorders (PDD) found in our sample and is there an overlap between these
conditions? Which factors or interventions were most helpful at hindsight and
what can we do to improve the care and treatment for patients with selective
mutism? To answer these questions the SM sample will be reassessed with
standardised instruments and validated neuropsychological measures and the
follow-up data will be combined with the data collected at the time of
referral.
INFORMATION ABOUT THE FAMILY, COMPONENTS OF TREATMENT, AND ANY PROBLEMS OR
RELAPSE AFTER TREATMENT IS COLLECTED USING QUESTIONAIRRES FOR THE PATIENT AND
HIS/HER PARENTS. IN ADDITION WE WILL FOCUS ON A GROUP OF BILINGUAL CHILDREN AND
WE WANT TO INVESTIGATE WHETHER DEMOGRAPHIC FACTORS OR GENETIC VULNERABILITY IS
A PREDICTOR. WE ALSO WANT TO INVESTIGATE WHETHER CHILDREN WITH SM HAS AN FIRST
OR SECOND DEGREE FAMILY MEMBER WITH ASD OR ASD-CHARACTERISTICS (SUCH AS
(COGNITIVE) RIGIDITY). WE BELIEVE THAT THIS ASPECT IS NOT INVESTIGATED BY
SYSTEMATIC INVESTIGATION AND WE EXPECT AN OVERLAP BETWEEN SM AND ASD.

Over the last decades, approximately 100 children with selective mutism have
been referred to our department. Clinical information and some standardised
data, such as CBCL and TRF scores and IQ data were collected and stored in
their clinical files. The study design will be an observational retrospective
cohort study. In addition to collecting information from the clinical files,
missing information about behavioural characteristics or psychiatric disorders
in the family, will be collected retrospectively at follow-up.
Follow-up data will be collected at least 2 years after treatment. To minimise
a sampling bias, all children referred to our department will be asked to
participate. However, it can be expected that a sampling bias will occur with
individuals with poorer outcome more likely to refuse participation than
individuals with better outcome. We hope to diminish any possible sampling bias
by carefully addressing all former patients and providing all participants with
good information. To minimise a measurement bias, we will use standardised
measurements (preferebly with Dutch population norms if appropriate) as much as
possible.
IF EX-PATIENTS PARTICIPATING IN RESEARCH THEY ARE INVITED TO COME TO OUR
DEPARTMENT FOR COMPLETING QUESTIONNAIRES AND PARTICIPATING IN
(NEURO)PSYCHOLOGICAL RESEARCH. IF THIS IS NOT FEASIBLE (EG IN RELATION TO AN
ANXIETY DISORDER), WE TRY TO DO THE RESEARCH IN A SAFE ENVIRONMENT FOR THE
PATIENT (EG HOME/SCHOOL). SOME OF OUR RESEARCH QUESTIONS WILL BE ANSWERED BY
OBSERVATIONAL AND DESCRIPTIVE DIMENSIONS (EG CURRENT FUNCTIONING, THE QUALITY
OF LIFE, PSYCHOPATHOLOGY AT FOLLOW UP, PSYCHOPATHOLOGY IN THE FAMILY). OTHERS
WILL BE ANSWERED BY USING QUANTITATIVE MEASURES (SURVEYS, NEUROPSYCHOLOGICAL
TASKS).

There are no benefits for the participants. There are also no risks associated
with any of the measures used. However, participating in a follow-up study can
be a burden to some of the participants. Some participants might not want to be
remembered to the treatment or difficulties in personal life. On the other
hand, if individuals still experience difficulties in life, it might also help
them to know that they are not the only ones, that a study is designed to
investigate these problems in themselves and others and that, in case they need
help, careful and professional help is available. We will offer clinical advice
to any individual that requires our assistance.
The burden of participation in terms of time and effort to complete the
questionnaires and neuropsychological test battery is moderate. We try however,
to do anything possible to minimize this burden, for instance offering to visit
them at home at a time or day that is most suitable for the participants. We
try to minimise anxiety levels by inviting them together with a parent, unless
they prefer otherwise. We also give participants who do not want to participate
in the part of the study that requires direct contact with staff, the
possibility to participate in part of the study by only filling out the
questionnaires.
At the end of the study all participants will be informed about the results on
INDIVIDUAL AND group level.