Topic H: Clinical psychology A2
- Syllabus
- 2026
- Topic
- —
- Level
- A2
Definitions of abnormality have moved from supernatural and moral explanations, through medical accounts, towards judgments that combine evidence about behaviour, distress and everyday functioning.
| Definition | Decision rule | Main limitation |
|---|---|---|
| statistical infrequency | behaviour or a score is rare in a population, often at least two standard deviations from the mean | rarity can be desirable, while common distress can still require help |
| failure to function adequately | the person cannot meet ordinary demands or experiences suffering, maladaptiveness or danger | functioning and expectations depend on the person, culture and context |
| Rosenhan and Seligman's indicators | suffering, maladaptiveness, irrationality, unpredictability, observer discomfort, unconventionality/vividness and violation of moral ideals form a pattern | no single indicator is necessary or sufficient, and observers can impose their values |
Earlier supernatural accounts could lead to punishment or exclusion. Medical classification reframed mental disorder as illness and encouraged treatment, while later psychological and social approaches emphasised cognition, learning, relationships, rights and individual experience. Each change can reduce one form of stigma yet create new labels.
Unusual appearance or high ability is not a disorder merely because it is statistically rare. A sound judgment considers distress, impairment, risk, duration, culture and the person's own context before deciding whether support or diagnosis is appropriate.
Classification systems organise symptoms into diagnostic categories so clinicians and researchers can communicate, select support and compare outcomes.
| System | Publisher and scope | Named syllabus versions |
|---|---|---|
| DSM | American Psychiatric Association; focuses on mental disorders and detailed diagnostic criteria | DSM-IV-TR and DSM-5 |
| ICD | World Health Organization; classifies all diseases and health conditions, including mental disorders, with international reporting codes | ICD-10 and ICD-11 |
Revisions respond to evidence and changing concepts. DSM-5, for example, combined several former autism diagnoses into autism spectrum disorder and added cultural-formulation guidance. ICD is designed for multilingual, international health reporting. Both use recognisable symptom patterns, but categories and thresholds can differ across manuals or editions.
A manual standardises the criteria; it does not make application automatic. Reliability requires different clinicians to reach the same diagnosis, while validity asks whether the category represents the person's disorder and predicts useful outcomes. A revised label may improve evidence or communication but can also disrupt comparisons with diagnoses made under an earlier edition.
A diagnosis is trustworthy only when clinicians apply criteria consistently and the resulting category accurately represents the person's difficulties in their cultural context.
| Issue | Question | Evidence route |
|---|---|---|
| inter-rater reliability | do different clinicians reach the same diagnosis? | independent interviews using the same criteria |
| criterion validity | do DSM and ICD or another accepted criterion agree? | compare diagnoses across systems |
| construct validity | do the criteria capture the disorder rather than an unrelated feature? | relate symptoms to converging measures and lived experience |
| predictive validity | does diagnosis predict course or treatment response? | longitudinal follow-up |
| cultural validity | is behaviour interpreted within the person's norms, language and meaning? | cultural formulation and culturally informed interviewing |
Culture can change how distress is expressed, whether hearing a voice has spiritual or clinical meaning, and how a clinician interprets language. Cooper et al. found New York psychiatrists more likely than London psychiatrists to diagnose schizophrenia from the same filmed interviews, illustrating possible system or cultural bias.
Clear manuals can increase agreement, but agreement on the same biased interpretation is reliable without being valid. Conversely, considering culture must not become a reason to dismiss genuine distress. Clinicians need standard criteria plus the person's meaning, impairment and context.
Schizophrenia involves disturbances of perception, belief and thought organisation; biological explanations identify risk mechanisms rather than a single inevitable cause.
| Symptom | Meaning |
|---|---|
| thought insertion | the belief that an outside source has placed thoughts in one's mind |
| hallucination | a perception without a corresponding external stimulus, often hearing voices |
| delusion | a strongly held belief that conflicts with available evidence and cultural context |
| disordered thinking | confused or loosely connected thought shown in speech that becomes difficult to follow |
The dopamine account links excess mesolimbic dopamine activity with positive symptoms and reduced mesocortical activity with negative or cognitive symptoms. Glutamate dysfunction at NMDA receptors may alter dopamine regulation and explain a wider symptom range. Drug and imaging evidence supports involvement, but changes measured after illness or treatment do not settle causal direction.
A genetic account proposes inherited vulnerability: risk rises with biological relatedness, yet identical-twin concordance is well below 100%. Rare mutations and brain-structure differences such as enlarged ventricles or reduced temporal-lobe volume are further candidates. No biological factor is sufficient; development, stress and social adversity can interact with vulnerability.
The syllabus permits unipolar depression or anorexia nervosa as the other disorder; each requires symptoms plus one biological and one non-biological explanation.
| Disorder | Core symptoms/features | Biological explanation | Non-biological explanation |
|---|---|---|---|
| unipolar depression | persistent low mood or loss of interest, impaired sleep, energy, concentration or functioning; major episodes may recur | monoamine accounts link disrupted serotonin/norepinephrine function and inherited vulnerability to risk | Beck's cognitive account links negative schemas, biased processing and the negative triad of self, world and future |
| anorexia nervosa | significantly low weight, restriction, fear of weight gain and distorted evaluation of shape/weight | genetic vulnerability and hypothalamic/neurotransmitter mechanisms may affect appetite, anxiety and reward | social learning and cognitive accounts explain attention to thin models, reinforcement and distorted body beliefs |
Antidepressant response and twin evidence support biological involvement in depression; cognitive bias and CBT response support a cognitive pathway. Twin evidence supports anorexia vulnerability, while Becker's Fijian television study supports a cultural-learning influence.
Treatment success does not prove the treated mechanism was the original cause. Neither disorder is a choice or a simple chemical imbalance: biology, learning, cognition and life context can interact, and symptoms require professional assessment rather than inference from one sign.
Drug therapy aims to reduce symptoms biologically, while family therapy changes the social environment and the family's ability to support recovery; they are often combined.
| Therapy | Main process | Strength | Limitation |
|---|---|---|---|
| antipsychotic drugs | typical agents mainly block dopamine D2 receptors; atypical agents such as clozapine or risperidone also affect other transmitters | can reduce hallucinations, delusions and distress quickly enough to support everyday functioning and further therapy | side effects, monitoring and non-adherence can reduce benefit; symptoms and people respond differently |
| family therapy | psychoeducation, communication and problem solving reduce conflict and help relatives recognise symptoms, support medication and plan for relapse | addresses patient and carer needs and can reduce relapse/readmission | time, access, engagement and family strain matter; it does not directly remove every biological symptom |
Risperidone and other antipsychotics have reduced positive and negative symptoms in treatment studies. Reviews of family interventions report improved social functioning and lower relapse; high criticism, hostility or emotional over-involvement is associated with greater relapse risk.
Medication is not merely chemical restraint, and family therapy does not blame relatives for schizophrenia. Effectiveness should include symptom change, functioning, side effects, adherence, relapse and the person's preferences—not only whether a drug altered dopamine.
For the optional disorder, drug therapy targets biological symptoms while CBT identifies and tests thought-behaviour patterns that maintain distress.
| Disorder | Drug therapy | CBT |
|---|---|---|
| unipolar depression | antidepressants such as SSRIs increase serotonin availability; change is delayed and side effects or relapse after stopping require monitoring | identifies negative automatic thoughts and schemas, tests evidence, schedules constructive activity and builds relapse-management skills |
| anorexia nervosa | medication may address co-occurring depression/anxiety or relapse risk after weight restoration, but evidence in the acute underweight phase is limited | CBT/CBT-E challenges rigid beliefs about food, weight and self-worth and changes avoidance, checking and restrictive routines alongside medical/nutritional care |
Combined antidepressant and CBT treatment can help some people with persistent depression. Routine-practice evidence from Hans and Hiller supports outpatient CBT but also shows meaningful dropout. For anorexia, CBT can improve beliefs and relapse outcomes, yet physical risk may first require coordinated nutritional and medical stabilisation.
Neither treatment is universally best. A person with severe low motivation may struggle with CBT tasks, while medication may reduce symptoms without changing maintaining beliefs or circumstances. Educational comparison is not a prescribing guide; diagnosis, safety, consent and individual response govern clinical decisions.
Rosenhan tested whether hospital staff could distinguish people without mental disorder from patients once a psychiatric label and setting shaped interpretation.
Eight pseudo-patients—five men and three women—sought admission to 12 US hospitals across five states. They reported an unfamiliar same-sex voice saying 'empty', 'hollow' and 'thud', while other personal details were largely truthful. After admission they stopped simulating symptoms, behaved ordinarily and recorded ward experiences in notes and diaries.
All were admitted and ordinary behaviour was often interpreted through the diagnosis. They reported depersonalisation, powerlessness, limited privacy and little staff contact. The range of public/private and old/new hospitals strengthens relevance to US inpatient care of that era; standardised presenting symptoms support comparison.
Real hospitals give ecological validity, but each ward usually had one observer, so emotional and interpretive bias could affect diaries. Staff were deceived and could not consent; admission may also reflect cautious risk management rather than inability to diagnose. The study exposed context and institutional treatment, not proof that every diagnosis or modern hospital is invalid.
Suzuki et al. assessed whether Japanese inpatients with schizophrenia showed different weight and nutritional status from healthy controls.
The sample contained 333 inpatients aged 16–80, diagnosed with DSM-IV-TR across nine psychiatric hospitals in Niigata Prefecture, and 191 healthy volunteers matched by age and sex. Height and weight produced BMI; fasting blood samples measured total protein, cholesterol, triglycerides and plasma glucose. Physical illness and recent drug-therapy changes were exclusion controls.
Underweight was more prevalent among the inpatients than in the general comparison group, while overweight/obesity prevalence was broadly similar. The findings support monitoring physical as well as mental health during long inpatient stays and reviewing food, activity and nutritional care.
Standard medical measures and matched controls improve objectivity and replicability, but BMI is not a complete measure of nutrition. Diet and exercise were not controlled, exclusion criteria reduce everyday representativeness, and nine hospitals in one Japanese prefecture cannot represent outpatients or other health systems. The group difference does not prove schizophrenia itself caused undernutrition.
Hans and Hiller asked whether outpatient CBT for adult unipolar depression remains effective—and how often people drop out—in ordinary clinical practice.
Their random-effects meta-analysis combined 34 non-randomised effectiveness studies of individual or group outpatient CBT. It calculated standardised mean gains at treatment end and six-month follow-up for depression severity, dysfunctional cognition, anxiety, distress and functional impairment, plus a weighted dropout rate. Results were benchmarked against high-quality RCTs.
Depression improvement was large for completers (d = 1.13) and intention-to-treat samples (d = 1.06); secondary outcomes showed moderate-to-large gains. Improvement was maintained six months after completion. Weighted mean dropout was 24.63%, and depression effects were smaller than benchmark RCT effects.
Explicit searches, eligibility rules and inter-coder checks strengthen reliability, while non-randomised routine-care studies improve ecological relevance. Yet studies varied in quality and design, causal alternatives remain, and completer results can exaggerate benefit. The conclusion is that CBT can transfer to practice, not that every patient completes or improves.
Ma, Quan and Liu tested whether perceived social support partly explains the association between core self-evaluation and depression.
A sample of 538 undergraduates—281 women and 257 men—completed standardised questionnaires measuring core self-evaluation, perceived social support and depression. Core self-evaluation covers broad judgments such as self-esteem and perceived competence. Correlations were entered into a mediation analysis to test whether support carried part of the self-evaluation–depression relationship.
Higher self-evaluation and greater perceived support were associated with lower depression, and social support was a partial mediator. This is consistent with a pathway in which more positive self-evaluation is related to perceiving or seeking support, which in turn relates to fewer depressive symptoms. 'Partial' means a direct association remained.
A large, standardised sample supports reliable comparison among undergraduates, but all variables were self-reported and may share response bias. The correlational design cannot establish that low self-evaluation caused low support and then depression; depression could change both ratings. Perceived support is also not the same as support objectively received, and students do not represent all people with unipolar depression.
Becker et al. examined whether prolonged exposure to television was associated with changing eating attitudes among ethnic Fijian adolescent girls in a previously media-naive setting.
A prospective multi-wave cross-sectional design compared separate schoolgirl samples in Nadroga: 63 participants in 1995, within weeks of television's introduction, and 65 in 1998 after three years of exposure. Both completed a culturally adapted 26-item Eating Attitudes Test; semi-structured interviews with a subset explored symptoms, body image and television meaning.
Indicators of disordered eating were significantly more prevalent in 1998. Interview narratives described dieting or weight loss as ways to resemble admired television characters and linked thinness with opportunity or success. Quantitative change and qualitative meaning converge on a plausible cultural-learning influence.
A naturally occurring change and standard measure give ecological value, but the design compared two cohorts rather than following the same girls. Television was not randomly assigned, so economic change, peers, tourism or other Western influence could confound the result. Small female samples from two schools limit generalisation, and association with disordered attitudes is not a diagnosis of anorexia nervosa.
Reichel et al. tested whether people with anorexia nervosa show an implicit appetitive response to extremely emaciated body images even when self-report does not reveal it.
Thirty-six adolescents/young adults with anorexia and 36 controls viewed images, including extremely emaciated bodies drawn from pro-anorexia sites. Candidate images were reduced from about 8,000; 36 were rated by a 100-person pilot and 16 selected. Acoustic probes elicited an eye-blink startle response measured physiologically, while participants also gave subjective ratings.
The anorexia group showed startle inhibition—interpreted as appetitive responding—to the extremely emaciated images, whereas controls showed startle potentiation, an aversive response. The groups did not show the same difference in subjective ratings. This divergence suggests implicit and reported emotional processing can differ.
Objective reflex recording and controlled stimuli support reliability, but interpretation of inhibition as attraction is theory-dependent. The small clinical sample limits generalisation, extreme images may cause distress, and a group difference cannot show whether the response caused or resulted from anorexia. The study concerns cue processing, not proof of addiction or treatment effectiveness.
Clinical methods must separate treatment effects from alternative explanations while protecting participants whose symptoms may affect risk, consent or withdrawal.
| Method | What it contributes | Critical boundary |
|---|---|---|
| randomised controlled trial | random allocation balances confounds; control/placebo or treatment-as-usual, baseline and follow-up permit outcome comparison; blinding reduces expectation bias | withholding established care may be unethical, attrition breaks balance and tightly selected samples may not reflect routine practice |
| structural scan (CAT/MRI) | produces images of anatomy, such as ventricles or tissue volume | a structural difference does not show moment-to-moment function or causal direction |
| functional scan (PET/fMRI) | maps metabolism, blood flow or oxygenation associated with activity during a task or state | an indirect signal and group association do not identify a thought or prove a disorder's cause |
| interview/self-report | captures symptoms, meaning and treatment experience | recall, demand, interviewer and social-desirability effects require triangulation |
A sound drug RCT pre-registers outcomes, obtains valid consent, records a baseline, randomly allocates through an independent process, standardises dose/contact, monitors adverse events and analyses all allocated participants where possible.
Calling a study randomised or using a brain image does not make its conclusion automatically causal or objective. Evaluate allocation, blinding, comparison, measurement, attrition, scan interpretation and clinical representativeness.
A published research report separates the question, procedure, evidence and interpretation so readers can audit how the conclusion was reached.
| Section | Main job |
|---|---|
| abstract | concise question, method, main result and conclusion |
| introduction | relevant theory/evidence and rationale |
| aims and hypotheses | precise intended test and predicted relationship/difference |
| method | design, sample, materials, procedure, ethics and analysis plan in replicable detail |
| results | descriptive and inferential findings without replacing data with opinion |
| discussion | interpret results, compare evidence, evaluate limits and applications, and propose justified next work |
Before publication, editors ask knowledgeable independent reviewers to judge contribution, methods, analysis, ethics, clarity and fit with the journal. Reviewers identify specific problems and recommend accept, revise or reject; authors respond and editors decide. Peer review can catch error and improve transparency.
Peer review is quality control, not proof that a claim is true. Reviewers can miss errors or share biases, and a well-structured report can still contain weak evidence. Replication, data transparency, later critique and evidence synthesis remain necessary after publication.
HCPC standards protect the public by setting threshold proficiency and ethical expectations for registered practitioner psychologists.
| Duty | Clinical meaning |
|---|---|
| safe scope and competence | recognise limits, refer when needed, maintain knowledge and continuing professional development |
| service-user interests | respect dignity, privacy, autonomy, culture and valid informed consent; safeguard where necessary |
| communication and records | communicate accessibly, keep accurate secure records and protect confidential information within legal limits |
| risk and candour | manage risk, report concerns, be open when something goes wrong and act to prevent harm |
| professional trust | maintain boundaries, declare conflicts, use evidence responsibly and ensure conduct justifies public confidence |
Practitioners must meet profession-specific proficiency standards to register and remain within the scope for which they are competent. The conduct, performance and ethics standards guide behaviour and are used when concerns are raised. Registration lets the public check professional status; failure to meet standards can trigger fitness-to-practise processes.
Fitness to practise means the person can practise safely, effectively and professionally, not that they never experience illness or make an error. It depends on competence, conduct, health management, insight and proportionate action in the actual scope of work.
Clinical data analysis begins with the research question and measurement level, then separates a sample description from an inferential decision.
| Job | Appropriate tool |
|---|---|
| describe centre/spread (List A) | mean, median or mode; range or standard deviation; percentages, ratios and fractions |
| display a pattern (List A) | frequency/summary tables, bar chart for categories, histogram for continuous distributions, scatter diagram for co-variables; inspect skew and impossible values |
| related difference (List B) | Wilcoxon signed-rank for paired or repeated scores |
| association (List B) | Spearman's rank for paired data that can be ranked |
| frequency association/difference (List B) | chi-squared for independent categorical frequencies |
For CBT sessions attended and number of anxious episodes, Spearman's rank fits because the hypothesis concerns association and both paired variables can be ranked. After calculating the statistic, use sample size, direction, significance level and the correct critical value to decide whether to reject the null.
A significant negative correlation can show that more sessions accompany fewer episodes, but it does not prove sessions caused the reduction: severity, motivation or another variable may influence both. Statistical significance is not clinical importance, and a table or graph must be read from its supplied values rather than reconstructed from missing data.
Clinical evaluation links a concrete method feature to the exact claim that becomes stronger or weaker, then states the bounded conclusion that survives.
| Criterion | Question | Topic H example |
|---|---|---|
| reliability | would procedure or scoring give a consistent result? | Suzuki's BMI/blood measures are replicable; Rosenhan's solo diaries lack inter-rater checking |
| validity | does the measure represent the disorder or treatment outcome? | EAT-26 standardises attitudes but is not an anorexia diagnosis |
| generalisability | do people and settings represent the target? | one Japanese prefecture or two Fijian schools narrows transfer |
| credibility/objectivity | are sources, coding and alternative explanations transparent? | reflex and blood measures reduce judgment; mediation and diary interpretations remain model-dependent |
| ethics | were consent, privacy, vulnerability and treatment risk managed? | deception in hospitals or distressing body images requires strong justification and safeguards |
| application | can the result improve care without exceeding evidence? | monitor inpatient nutrition; do not claim schizophrenia itself caused low weight |
The same feature can cut both ways: non-randomised routine CBT studies improve ecological validity but weaken causal control; a scanner offers objective output but interpretation may remain uncertain. Triangulation is strongest when methods address complementary weaknesses.
A weakness narrows population, mechanism or certainty; it does not automatically erase the study. Finish by naming what is supported, under which conditions, and what remains unproven.
A content analysis converts words, images or audio from at least two real sources into systematic evidence about attitudes to mental health.
Credibility depends on who created each secondary source, for what audience and purpose, and whether length, format and date are comparable. Public availability does not remove privacy or stigma risk: avoid exposing identifiable vulnerable people, reproduce only necessary material and frame categories without reinforcing harmful labels.
Real media give ecological validity and archived sources permit change-over-time comparison. Yet category judgment can be subjective, word counts lose context and a small search-engine sample cannot represent all media. Predefined rules, independent coding, an agreement statistic, broader source sampling and a recorded audit trail improve reliability. Results must describe the actual coded sources, not invented example percentages.