There are a lot of similarities between developmental disorders (e.g. DSD, autism). Neurodevelopmental disorders have a proven biological basis (e.g. ADHD) and behaviour and emotion disorders do not have a proven biological basis and it is likely that the environment is more important for these disorders.

It is important to assess how complaints could develop for the child, the parents and their parenting. This is the construct-centred approach. This focuses on the factors that have to do with the problem behaviour.

A difficulty learning can lead to difficulties in school and this can lead to plenty of problems in childhood. There are several practical problems when interviewing children:

• Repetition of question leads to a change of answer.
• Children are sensitive to suggestive questions.
• Children perceive questions about thoughts, emotions, worries and fears as unpleasant.
• Children have a limited self-reflection.
• Children have a limited memory.
• Children are loyal to parents and other adults.

There are several reasons to still interview the child despite the practical problems:

• It is important to understand the adult who registered the child.
• It is important to understand the attitude of the child.
• It can determine the severity of the complaints.
• It can determine whether the problems are specific to a situation.
• It gives the child the idea that he is being taken seriously.
• The child can bring up information he does not reveal in front of parents.
• The child is an informant.

It is important to use multiple informants when working with children. This is important because:

• It provides unique information about the psychological context.
• It solves a child’s potential inability to answer a question.
• The perspective of third parties is informative.

The child behaviour checklist (CBCL) checks internalizing (1), externalising (2) and other problems and symptoms. The diagnosis cannot be based on the screener of these types of symptoms. There are different explanations for the differences between informants:

• Bias through differences in motivation.
• Behaviour depends on the situation or context.
• Differences in frame of reference.
• Differences in access to information (i.e. information about the child’s behaviour).
• Different view (e.g. about what is normal).

Observation refers to perceiving for the purpose of drawing conclusions. However, this is made difficult because of selectivity (1), subjectivity (2), absence of base rate and norms (3) and (in)stability of perception (4).

The systematic / standardized approach reduces these problems by logging the what, when and where of the perceptions. The content of observation requires choosing the observation unit. Molecular observation refers to a very specific observation which is not very meaningful but objective and highly reliable. A molar observation refers to a general observation which is meaningful but less objective and less reliable. Professional observation refers to goal-oriented observation on the basis of an observation question which leads to an informed decision to act. The logic error refers to the tendency to pass similar judgements on traits that seem to be logically linked instead of forming an isolated impression.

It is possible to observe people in the laboratory (1), in a simulated setting (2) and the natural environment (3). The simulated setting requires the client to complete an assignment in the natural environment which allows the researcher some form of control.

Disadvantages of observation in natural surroundings are the investment of time and the information is not necessarily comparable. The disadvantages of observation in a laboratory setting are potential low validity, it is very time-consuming and requires specialized equipment. Observation in simulated settings has a high validity and allows for comparisons with other clients.

Behavioural observation gives information and possible antecedents of behaviour. It can be conducted formally and informally although reactivity is an issue. It provides a direct collection of relevant evidence on the child’s behaviour but it misses relevant internal states that play a role in the child’s functioning.

Event sampling refers to observing when the behaviour occurs. This is preferred when the frequency of the behaviour is relatively low. The duration and the quality of the behaviour can also be scored. Time sampling refers to observing the behaviour at a fixed time. This is preferred when the frequency of the behaviour is high.

Self-observation requires the behaviour to be observed to be very clearly defined. It is suitable for measuring the frequency and nature of the occurrence of problem behaviour and for behaviour that is not visible to others. It is valid but not necessarily reliable. The behavioural avoidance test is used for the observation of avoidance behaviour. It consists of compiling a list of situations with which the client has difficulties. The client then arranges these situations according to difficulty.

Emotions and skills develop during childhood which makes standard tables by age group essential (i.e. age-related norm groups). There are several steps in combining sources:

1. Document all important data about all constructs and of all informants.
2. Look for patterns.
3. Attempt to understand the discrepancies.
4. Create a hierarchy of problems.
5. Determine the ranking of the information in the report (i.e. what is given more and less weight).

Primary problems are problems that are a core of the problem. Secondary problems are a consequence of the primary problems. The results of tests (1), conclusions (2) and information about third parties (3) go into the psychological report. Construct-focused testing means that there is a focus on the primary and secondary problems and their apparent underpinnings.

A child does not have right of access to the psychological report up until the age of 12. Up to the age of 16, the report should be discussed with legal representatives unless it would damage the interests of the child. From the age of 16, the child should fully be involved in feedback unless the child cannot be considered capable.

The psychological report should be sent to parents first. It should not immediately be sent to the ordering client and this can be blocked by the child and the representatives. However, this is not allowed if the assessment was issued by law. The psychological report should only be sent to the school with parental consent. It should only be sent to the child if the child is old enough.

In the case of divorced parents, both parents have legal rights (1), are informants (2) and care about the child (3). The model of evidence-based assessment is guided by three principles:

1. Every decision made during assessment should be guided by the most current and best available research.
2. Results from tests should be used only for making interpretations for which they have been validated.
3. The assessment procedure should be guided by a hypothesis-testing approach (i.e. address the referral question by developing hypotheses based on research).

The criteria by which treatment progress is evaluated should be measurable (1), the criteria should be sensitive to change (2), the criteria should be meaningful (3) and the criteria should be feasible (4). Meaningful outcomes can be established using baseline data on the referral issues. The development context of the child should be taken into account when choosing instruments.

Clinical utility refers to the extent to which a measure will make a meaningful difference in relation to diagnostic accuracy, case formulation considerations and treatment outcomes. Incremental validity refers to the extent to which a measure provides unique additional information that aids in the assessment process.

It is essential that the assessment of a child has multiple informants who interact with the child in different settings and who may have different perceptions of the child’s adjustment. Parent reports are useful but may be less useful over time (1), may be influenced by psychopathology (2) and may be influenced by the view that the parent takes regarding the child. Teacher reports are useful but teachers are less likely to observe anti-social behaviour (1), the usefulness of the teacher report depends on age (2) and older children are likely to have multiple teachers (3).

Peers provide a unique perspective on the child’s social functioning and may reveal interpersonal issues that inform intervention efforts. However, it is rarely used due to time constraints (1), limited access (2) and ethical constraints (3). Institutional records (i.e. school, detention centre) can provide a clear indicator of impairment in the setting from which the records are obtained.

Expressed emotionality is a system that provides information about the degree of criticism and emotional over-involvement in a family member’s attitude towards a client. It is used for insight into the risk of psychotic relapse in a client with schizophrenia.