5 Organisation and delivery of psychiatric services5.4 Assessing the need for psychiatric services
5.4 Population needs assessment, service design and costs
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Written by Resident Doctor Committee · Published
Stevens and Raftery's approaches to needs assessment
Approach | Method | Weakness |
|---|---|---|
Epidemiological | Estimates need from incidence, prevalence, severity and treatment effectiveness | National or trial figures may not fit local need |
Comparative | Benchmarks provision and outcomes against similar populations | Matching an under-resourced service copies its shortfall |
Corporate | Consults patients, carers, clinicians and commissioners | Excluded groups go unheard |
Bradshaw's types of need
Type | Defined by |
|---|---|
Normative | Professional or expert standards |
Felt | The person's own perception |
Expressed | A request for help, such as consulting a general practitioner (GP) |
Comparative | Differences from similar populations |
Bradshaw classifies the basis of a claim to need, whereas Stevens and Raftery's comparative approach is a method of estimating need by benchmarking.
Need is the population's requirement for beneficial care, including people unknown to services, whereas demand is requests for care.
A waiting list measures demand against capacity, not need, so poor access can keep it short while unmet need is large.
Measuring deprivation and social class
The Jarman index (underprivileged area score) measures community-level social deprivation from census variables weighted by GPs' judgements of workload, as a proxy for local need.
The National Statistics Socio-economic Classification (NS-SEC) has eight analytic classes based on occupation and employment relations, not hours worked or other labour-market labels.
NS-SEC has no separate skilled manual class, because it dropped the manual and non-manual divide of the old Registrar General's Social Class.
Population surveys and prevalence
The Adult Psychiatric Morbidity Survey (APMS) samples adults living in private households in England and detects disorder whether or not it has been treated. Eligibility depends on type of residence, not age, diagnosis or service contact, so people in prisons and other institutional or communal settings fall outside it.
Measure | Figure |
|---|---|
Common mental disorder in the past week (2014) | One in six adults (17%): women near one in five, men near one in eight |
Common mental disorder over a year or a lifetime | One in four |
Adults with common mental disorder in current treatment | About one in three (37%) in 2014, against about 24% in 2007, so most go untreated |
Hallucinations in a given year (APMS series) | About 4% of adults, even after excluding psychotic disorder |
Major depressive disorder in adults consulting in primary care | 5% to 10%, about 8%, at any one time |
Dementia at 65 and over (point prevalence) | About 7% (one in fourteen), doubling with each five years of age; one in six at 80 and over |
Postnatal depression | One woman in ten in the year after birth |
Any mental health problem in pregnancy or the first postnatal year | One woman in five |
Contact with secondary mental health, learning disability and autism services, England 2021/22 | About 3.25 million people, 5.8% of the population (one in seventeen) |
Ethnicity and incidence: AESOP
AESOP is the UK study of first-contact incidence of psychosis by ethnic group within defined catchment areas.
It found the greatest excess of bipolar affective disorder in the Black Caribbean group, with Black African rates also raised but less so.
Pathways to care
Goldberg and Huxley's levels and filters model describes five levels and four filters on the pathway to psychiatric care, each filter being the decision point between successive levels.
In community data, the mean interval from onset of major depression to first treatment is just under four years.
In the World Health Organization World Mental Health surveys (Wang and colleagues, 2007), delay to first treatment contact is longer with developing-country residence, older birth cohort, male sex and earlier age of onset.
Delay in those surveys is longer for anxiety disorders than for mood disorders.
Service design and costs
A service specification sets aims, eligibility, staffing matched to case volume and complexity, referral and discharge arrangements, separate crisis capacity and outcomes defined before opening.
Staffing is usually the largest recurring cost, and inpatient care has high daily costs, mainly from round-the-clock staffing.
Opportunity cost is the best alternative forgone when resources are spent elsewhere.
Commissioning is a repeated cycle of assessment, design, delivery, monitoring and review.