Cohen (2018). Personality assessment methods

Objective methods of personality assessment typically contain short-answer items for which the person being assessed needs to select a response. The answers of questions is indicative for the presence or absence of a personality trait. However, these methods are prone to response biases and the content of the items can be guided by theory.

The sign approach states that test responses are deemed to be signs or clues to underlying personality or ability. The sample approach states that behaviour is to be interpreted in light of a trait of interest. An advantage of the sign approach is that the client might become aware of feelings that one was not previously aware of.

Behavioural assessment refers to what a person does in situations rather than on inferences about what attributes this person has. In traditional approaches to assessment, data is used to diagnose and classify, whereas in behavioural approaches to assessment, data is used to describe targeted behaviours and maintaining conditions usually for the purpose of selecting specific therapeutic conditions.

In traditional assessment, an individual’s behavioural history is afforded great weight (i.e. it is seen as predictive of future behaviour). In behavioural approaches, behavioural history provides a baseline information relevant to an individual’s learning history.

There are several questions that can be asked in behavioural assessment:

1. Who
   This refers to the question of who the assessee and who the assessor is. In behavioural assessment, the assessee can be the assessor (e.g. diaries).
2. What
   This refers to the question of what is being measured in the behavioural assessment. This typically constitutes of targeted behaviour which is measurable (e.g. amount of times face touched).
3. When
   This refers to the question of when the assessment of behaviour is made. Assessment of behaviour is typically made at times when the problem behaviour is most likely to be elicited (e.g. during lunch). It can also occur through frequency or event recording (i.e. each time the behaviour occurs) (1) or interval recording (i.e. assessment according to pre-defined schedules). The intensity of the behaviour may also be measured.
4. Where
   This refers to the question of where the assessment takes place. In behavioural assessment, this can be anywhere, preferably the environment in which the target behaviour is most likely to occur.
5. Why
   This refers to the question of why the assessment takes place. This can take place to provide behavioural baseline data (1), to provide a record of the assessee’s behavioural strengths and weaknesses across a variety of situations (2), to pinpoint environmental conditions that are acting to trigger, maintain or extinguish certain behaviours (3), to target specific behavioural patterns for modification (4) and to create graphic displays useful in stimulating innovative or more effective treatment approaches (5).
6. How
   This refers to the question of how the assessment is conducted. This depends on the goal of the assessment.

Timeline followback (TLFB) methodology refers to a method of recording the frequency and intensity of target behaviour. Ecological momentary assessment refers to recording behaviour-related events as they occur through a handheld computer to maintain an electronic diary of the behaviour.

There are several varieties of behavioural assessment:

1. Behavioural observation and rating scales
   This technique involves watching the activities of targeted clients and maintain some kind of record of those activities. It can also make use of a behaviour rating scale, which is a pre-printed sheet on which the observer notes the presence or intensity of targeted behaviours.
2. Self-monitoring
   This technique involves the act of systematically observing and recording aspects of one’s own behaviour and/or events related to that behaviour. One relevant aspect of this is reactivity, the possible changes in an assessee’s behaviour, thinking or performance that may arise in response to being observed, assessed or evaluated.
3. Analogue studies
   This technique involves a research study in which one or more variables are analogous to the real variable of interest.
4. Situational performance measure (analogue approach)
   This technique involves a procedure that allows for observation and evaluation of an individual under a standard set of circumstances (e.g. road test).
5. Leaderless group technique (analogue approach)
   This technique involves a group of several people who have to carry out a task as an observer records information related to individual group members’ initiative, cooperation, leadership and other related variables.
6. Role play
   This technique involves acting an improvised or partially improvised part in a simulated situation.
7. Psychophysical methods
   These techniques involve physiological measures that are thought to be influenced by psychological factors.
8. Unobtrusive measures
   These techniques do not necessarily require the presence or cooperation of respondents when measurements are being conducted (e.g. look at garbage).

Behaviour rating scales can be categorized according to a continuum of direct to indirect. This applies to the setting in which the observed behaviour occurs and how closely that setting approximates the setting in which the behaviour naturally occurs. The more natural the setting, the more direct the measure. Broad-band instruments are designed to measure a wide variety of behaviours and narrow-band instruments are designed to measure on behaviours related to specific constructs.

Analogue behavioural observation refers to the observation of a person or persons in an environment designed to increase the chance that the assessor can observe targeted behaviours and interactions.

Biofeedback refers to a class of psychophysical assessment techniques designed to gauge, display and record a continuous monitoring of selected biological processes (e.g. blood pressure). The plethysmograph is a biofeedback instrument that records changes in volume of a part of the body from variations in blood supply.

The contrast effect refers to an excessively positive rating because the previous rating was excessively negative. Composite judgement refers to the average of multiple judgements of multiple raters. Other issues of behavioural assessment are equipment cost, cost of training of behavioural assessors and the operationalization of certain (personality) traits.