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Department of Psychiatry, St George's Hospital Medical School, Cranmer Terrace, Tooting, London SW17 0RE
School of Public Policy, University College London
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Abstract |
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We retrospectively investigated the association between the Jarman and Townsend indices of deprivation and referral rates to community mental health teams (CMHTs) and in-patient admissions rates, including the contribution of general practice factors to these rates. The samples consisted of all community/out-patient referrals and admissions to four CMHTs over 1 year.
RESULTS
Low positive correlation was found between community/out-patient referral rates for all diagnoses and psychosis with the Jarman index, and between both the indices and admission rates for all diagnoses and non-psychosis. Referrals from general practitioners (GPs) varied nearly 40-fold and were not related to either indices, fundholding status or having practice manager or practice nurse.
CLINICAL IMPLICATIONS
Overall, the Jarman index appears to be a more useful index for planning psychiatric service provision. However, because of the small correlation with referral and admission rates, deprivation indices in themselves would be of limited value, as there may be other relevant factors that require investigating. GP characteristics investigated did not predict referral rates.
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Introduction |
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Method |
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The data collected on each patient in both groups included postcode, whether the patient was seen/ assessed, whether the patient was taken on for treatment or referred back, diagnostic category and profession of keyworker. Additional data collected on the in-patient sample included Mental Health Act use and length of stay in hospital. A Jarman index and a Townsend material deprivation index was allocated to each patient by linking his/her postcode to a census enumeration district (Majeed et al, 1995). Out-patient referral rates and in-patient admission rates were calculated by using the number of patients in each enumeration district as the enumerator and the total population of the enumeration district as the denominator. Using information from the local authority, each practice's referral rate to the four CMHTs was also calculated. Practices with less than 1000 patients were excluded from this analysis.
Statistical tests used were as follows:
2 test for
categorical data, unpaired t-test for normally distributed continuous
data, MannWhitney U test (for two category variables) and
KruskalWallis test (for more than two category variables) for
non-normally distributed continuous data and Spearman's correlation for
analysing correlations between the indices of deprivation and the referrals
and admissions rates (as both the referral and admission rates included 0
rates for several enumeration districts, resulting in considerable deviation
from normal distribution). The Statistical Package for Social Sciences for
Windows, 6.1 was used for analysis (SPSS, 1994).
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Results |
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Seventy-five per cent of the assessed patients did not have psychoses (ICD-9 categories 300-316), 21% had psychoses (ICD-9 categories 290-299) and 4% were non-cases (World Health Organization, 1978). Non-psychotic disorder was significantly more common in women (80% compared to 68% in men) and psychotic disorder in men (28% compared to 16% in women; P<0.001). The proportion of referrals with and without psychotic disorder across the teams was not significantly different.
Admissions
There were 321 (54% men) in-patient admissions. Seventeen per cent of the
admissions were involuntary but varied significantly from 11-30% between the
CMHTs (P=0.01). The ratio of patients with or without psychoses for
admissions was almost the reverse of that of community/out-patient referrals,
31% had non-psychotic disorders and 69% psychotic disorders. The proportion of
admissions with or without psychoses across the CMHTs was not significantly
different (P=0.57). More women had a non-psychotic disorder (35%
compared to 27%) and more men had a psychotic disorder (73% compared to 63%),
but these differences were not statistically significant (P=0.23).
Mean length of stay of in-patients was 41 days (median=21, range 1-423).
Length of stay was not significantly different between the CMHTs
(P=0.17). The psychotic group had a longer length of stay (mean 50
days, median 33 days) than the non-psychotic group (mean 29 days, median 8)
(P<0.0001).
Correlation between deprivation indices and referral and admission
rates
The unit of analysis for correlation between indices of deprivation and
area rates of referrals and admissions was the enumeration district. The
enumeration district was preferred to the electoral ward as the unit of
analysis because the latter would have reduced the sample size to 16. Also, as
enumeration districts are substantially smaller than electoral wards,
misclassification bias owing to the ecological fallacy is less likely to
occur.
The four CMHTs served 271 enumeration districts. The mean Jarman index for these 271 enumeration districts was 6.1 (range -37.0 to 83.5) and the mean Townsend index was 0.2 (range -6.1 to 8.7). The mean crude community/out-patient referral rate per 1000 population per enumeration district for all patients was 7.8 (range 0-41). For referrals with psychoses it was 1.2 (range 0-24) and referrals without psychoses it was 4.6 (range 0-25). The mean crude in-patient admission rate (per 1000 population) per enumeration district for all patients was 2.6 (range 0-26); for admissions with psychoses, 1.1 (range 0-14), and admissions without psychoses, 0.42 (range 0-6).
There was a low positive correlation between overall community/out-patient
referral rates and the Jarman index (
=0.13, P<0.05), but not
with the Townsend index. There was low positive correlation between
community/out-patient referral rates for psychosis and the Jarman index
(
=0.17, P<0.01) and the Townsend index (
=0.15,
P<0.05). There was no significant correlation between either of
the indices and community/out-patient referral rates for non-psychosis. There
was a low positive correlation between both the indices and admission rates
for all diagnosis and non-psychosis (Table
2). There was no significant relationship between both the indices
and admission rate for psychosis.
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GP referral rates
There was a nearly 40-fold variation in general practice referral rates to
the four CMHTs, from 0.26-10.2 per 1000 patients aged 16-64 years (practices
with fewer than 1000 patients excluded). There was a non-significant negative
correlation between the Townsend index for the practice and the referral rate
to CMHTs (R=-0.30, P=0.10). There were no significant
differences in referral rates between practices with and without a practice
manager or practice nurse or between fundholding and non-fundholding general
practices.
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Discussion |
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The Jarman index was consistently positively associated with a number of measures of psychiatric morbidity, including community/out-patient referral rate for all diagnoses and for illness; and admission rates for all diagnoses and non-psychosis. However, the correlation coefficients were relatively low. The Townsend index showed similar low positive correlations with admission rates for all diagnosis and psychosis, but was only significantly correlated with community/out-patient referral rates for psychosis.
Our findings suggest that both Jarman and Townsend indices would be moderately useful for planning in-patient provision. For planning community/out-patient services, the Jarman index seems more useful than the Townsend index. Hence, given the wide coverage by the CMHT model (Johnson & Thornicroft, 1993) in the UK (where the same team is responsible for both in-patient and community care), the Jarman index would be the indicator of choice. Its value is further enhanced by its ready availability at enumeration district level.
Such a detailed and flexible prediction of workload is of increasing importance in the context of the reorganisation of primary care and the requirement for coordination with secondary mental health services. The other important area that needs to be addressed in planning community psychiatric services is links with primary health care teams, particularly in ensuring that teams make appropriate use of services. For some primary health care teams, this may mean increasing their referrals to community psychiatric services. However, neither the Jarman index nor Townsend index performed as well as was expected. This may be partly owing to some of their constituent variables being inappropriate for the purpose. The more recently developed Mental Illness Needs Index (MINI) appears to be an improvement, containing epidemiologically more meaningful variables for prediction of admission, at both local and regional levels (Glover et al, 1998). This also deserves more extensive investigation in relation to both admission and referrals rates.
This study has a number of limitations. It uses retrospectively collected data from case notes and the comparison of psychiatric morbidity and socio-economic factors used an ecological design. The relatively low correlations between deprivation and referral and admission rates may reflect the importance of a range of other factors at the primarysecondary care interface. CMHTs increasingly have well-established liaison with local GPs (Strathdee & Williams, 1984; Burns & Bale, 1997), which profoundly affects these rates. The therapeutic style of individual consultants and their teams has also been shown to impact admission rates (Croudace et al, 1997).
Most of the previous research on the association between psychiatric workload and socio-economic factors has concentrated on admission rates. Now that most of the workload of psychiatry services takes place in the community, more research is needed on community and primary care services for psychiatric disorders, and on factors that predict psychiatric workload in the community.
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References |
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CARR-HILL, R. A., HARDMAN, G., MARTIN, S., et al (1994) A Formula for Distributing NHS Revenues Based on Small Area use of Hospital Beds. York: Centre for Health Economics, University of York.
CROUDACE, T., BECK, A. & HARRISON, G. (1997) Profiling activity in acute psychiatric services. Journal of Mental Health, 7, 49-57.
JARMAN, B. (1983) Identification of underprivileged areas. BMJ, 286, 1705-1709.
JARMAN, B. (1984) Underprivileged areas: validation and distribution of scores. BMJ, 289, 1587-1592.
JARMAN, B., HIRSCH, S., WHITE, P., et al (1992) Predicting psychiatric admission rates. BMJ, 304, 1146-1151.
JOHNSON, S. & THORNICROFT, G. (1993) The sectorisation of psychiatric services in England and Wales. Social Psychiatry & Psychiatric Epidemiology, 28, 45-47.[Medline]
GLOVER, G. R., ROBIN, E., EMAMI, J., et al(1998) A needs index for mental health care. Social Psychiatry & Psychiatric Epidemiology, 33, 89-96.[CrossRef][Medline]
MAJEED, F. A., COOK, D. G., POLONIECKI, J., et
al(1995) Using data from the 1991 census.
BMJ, 310,
1511-1514.
MELZER, D., WATTERS, L., PAYKEL, E., et al(1999) Factors explaining the use of psychiatric services by general practices. British Journal of General Practice, 49, 887-891.
SMITH, P., SHELDON, T. A. & MARTIN, S. (1996) An
index of need for psychiatric services based on in-patient utilisation.
British Journal of Psychiatry,
169,
308-316.
STRATHDEE, G. & WILLIAMS, P.(1984) A survey of psychiatrists in primary care: the silent growth of a new service. Journal of the Royal College of General Practitioners, 34, 615-618.
THORNICROFT, G. (1991) Social deprivation and rates of
treated mental disorder. Developing statistical models to predict psychiatric
service utilisation. British Journal of Psychiatry,
158,
475-484.
THORNICROFT, G., BISOFFI, G., De SALVIA, D., et al (1993) Urbanrural differences in the associations between social deprivation and psychiatric service utilization in schizophrenia and all diagnoses: a case-register study in Northern Italy. Psychological Medicine, 23, 487-496.[Medline]
TOWNSEND, P., PHILLIMORE, P. & BEATTIE, A. (1988) Health and Deprivation: Inequality and the North. London: Croom Helm.
WORLD HEALTH ORGANIZATION (1978) Mental Disorders: Glossary and Guide to their Classification in Accordance with the Ninth Revision of the International Classification of Diseases. Geneva: WHO.
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