Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar...

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Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004

Transcript of Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar...

Page 1: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Researching ethnic differences in health: finding the right data

Mark Brown, CCSR

CCSR Seminar Series: 2004

Page 2: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Ethnic differences in health

Context…

1999 study of Black and Minority Ethnic Housing needs in Manchester

Health emerges as a key issue

Motivation for a more systematic investigation – using survey data

1999 Health Survey for England (with a boosted B&ME sample)

Page 3: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Ethnic differences in health

Presentation… an exemplar of the problem of small samples

in surveys

a new appreciation of the census

Page 4: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Ethnicity and health

Long literature but little consensus

about nature or extent of ethnic differences

explanations for those differences

Page 5: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Explaining ethnic differences

Ethnic differences in health status

Explanation

Artefact

Material

Cultural

Migration

Genetic

after controlling for age

Page 6: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Ethnicity and health research questions with obvious policy relevance

are service needs among B&ME groups different? • in scale? • in the nature of need? • in terms of appropriate forms of delivery?

heightened interest in light of an ageing population

Page 7: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Ageing minorities Aged 60+

Aged 75+

1991 %

2001 %

% increase

1991-2001

1991 %

2001 %

% increase

1991-2001

White 22.2

22.1 0.6 7.5 8.2 10.3

Non-white

5.9 8.0 108 0.8 1.5 175

Indian 6.8

10.2 86 1.2 2.0 119

Pakistani

3.7 6.6 179 0.4 1.1 340

Bangla 3.3 5.9 312 0.2 0.6 457

Page 8: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Contrasting age structures

-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1

0 years

4 years

8 years

12 years

16 years

20 years

24 years

28 years

32 years

36 years

40 years

44 years

48 years

52 years

56 years

60 years

64 years

68 years

72 years

76 years

80 years

84 years

88 years

Series2

Series1

-1.5 -1 -0.5 0 0.5 1 1.5

0 years

4 years

8 years

12 years

16 years

20 years

24 years

28 years

32 years

36 years

40 years

44 years

48 years

52 years

56 years

60 years

64 years

68 years

72 years

76 years

80 years

84 years

88 years

Series2

Series1

General Pakistani

Page 9: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Measuring health differences: data issues

Reliance on country of birth statistics (relatively recent adoption of ethnicity in population and health statistics)

Small numbers - especially in national sample surveys e.g. General Household Survey - B&ME sample <1000 hs

Page 10: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

But a growing interest in ethnic comparisons... surveys designed to facilitate analysis of ethnic

difference

• 1994 PSI National Survey of Ethnic Minorities (B&ME sample size > 5,000)

• 1999 Health Survey for England (HSE) (B&ME sample size = >8,000)

bigger samples

B&ME specific questions

Page 11: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

1999 Health Survey for England

Aim to compare ethnic groups

for selected measures of health (mental as well as physical health)

age dimension - health better or worse for the B&ME elderly?

Page 12: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Why the Elderly?

The demographic situation: Asian elderly ‘time bomb’

evidence of a deprived and needy group hard living conditions - overcrowding poor physical health - heart disease, stress

related illness loneliness, cultural alienation suffering a ‘double’ or even ‘triple jeopardy’

(being in a poor environment, being old, being non-white)

Page 13: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Why Mental wellbeing?

Case for a broad definition of health - taking in mental wellbeing / happiness / quality of life - especially among frail elderly

impact of factors such as overcrowding and cultural alienation on health likely to be psychological as much as physical

topical… Bennett Inquiry…

Page 14: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Why Mental wellbeing?

Bennett Inquiry, 2004:

‘Many mental patients face difficulties in accessing appropriate treatment, but black and ethnic minority communities suffer by far the most serious problems’

Guardian Leader

Page 15: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Measuring psychological wellbeing in a survey? General Health Questionnaire 12 (GHQ 12)

designed to detect possible psychiatric morbidity

12 questions about general levels of happiness, depression, anxiety and sleep disturbance over the past four weeks.

a score of 4 or more used to identify informants with a possible psychiatric disorder

but question over validity for B&ME groups

Page 16: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Ethnic differences? Figure from main report

Page 17: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Ethnic differences?

Statistically significant differences after controlling for age

Bangladeshi men twice as likely to have a high GHQ12 score

But what relationship with age?

Masked by standardisation

Page 18: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

From the Official 1999 HSE report...

“In the general population, the proportion with a high GHQ12 score did not vary much with age, but among men of South Asian origin and Black Caribbean men, it appeared to increase with increasing age... However, the samples of each sex in the oldest age group (55 and over) were small, and should be treated with caution.”

Report generally offers very little detailed analysis by age... but this is vital information

• for the description of difference• for understanding difference• in terms of a policy response?

Page 19: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

High GHQ12 score: % by age by ethnic group (men)

0

10

20

30

40

50

60

General BlackCaribbean

Indian Pakistani Bangladeshi Chinese Irish

16-34 35-49 50-64 65+

Page 20: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

High GHQ12 score: % by age by ethnic group (men)

0

10

20

30

40

50

60

General BlackCaribbean

Indian Pakistani Bangladeshi Chinese Irish

16-34 35-49 50-64 65+

34 cases

12 cases

Page 21: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

High GHQ12 score: % by age by ethnic group (men)

0

10

20

30

40

50

60

General BlackCaribbean

Indian Pakistani Bangladeshi Chinese Irish

16-34 35-49 50-64 65+

34 cases

12 cases

Page 22: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

High GHQ12 score: % by age by ethnic group

Striking differences, but... Based on very small numbers. Standard errors are big; overlapping confidence

intervals

Response: do some heavy re-coding on age on ethnic group sexes combined

at what price?

Page 23: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

High GHQ12 score: % by age by ethnic group (men)

reduced detail on age

0

10

20

30

40

50

60

General BlackCaribbean

Indian Pakistani Bangladeshi Chinese Irish

16-34 35-54 55 +

76 cases51 cases

Page 24: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

0

10

20

30

40

50

60

General BlackCaribbean

Indian Pakistani Bangladeshi Chinese Irish

16-34 35-54 55 +

High GHQ12 score: % by age by ethnic group (women)

reduced detail on age

28 cases38 cases

Page 25: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

High GHQ12 score: % by age by ethnic group (women) reduced detail on ethnic group

0

10

20

30

40

50

60

General Black Caribbean Indian Pak&Bang Chinese Irish

16-34 35-49 50-64 65+

18 cases

Page 26: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

High GHQ12 score: % by age by ethnic group (women)

reduced detail on age and ethnic group

0

10

20

30

40

50

60

General Black Caribbean Indian Pak&Ban Chinese Irish

16-34 35-54 55 +

66 cases

Page 27: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

High GHQ12 score: % by age by ethnic group (men)

reduced detail on age and ethnic group

0

10

20

30

40

50

60

General Black Caribbean Indian Pak&Ban Chinese Irish

16-34 35-54 55 +

127 cases

Page 28: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Statistical significance: at a price?

Recoding to retain adequate sample size --> A blurring/changing of the story

Masks diversity

generates groupings that are conceptually and theoretically unsound:

A single over 55 category for the elderly? Pakistanis and Bangladeshis combined

Page 29: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

1994 National Survey of Ethnic Minorities: the same story

Table 1 Relative risk of ‘fair or poor self-reportedhealth’ among ethnic minorities compared with whites

Caribbean Indian/AfricanAsian

Pakistani/Bangladeshi

All ethnicminorities

Age & sex 1.25 0.99 1.45 1.17

Standardof living,age & sex

1.15 0.94 1.24 1.08

(Data reproduced from Berthoud et al 1996)

Page 30: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Observations Even in targeted surveys, small sample size is a

far greater barrier to the researcher than the conceptual or operational crudeness of variable definitions

strategies to retain adequate sample size mean we never get near exploiting the full detail available in the variables

not even able to properly describe the differences I wanted to explain

Page 31: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Census to the rescue? Commissioned tables from the 2001 Census

Long Term Limiting Illness by Age by sex by ethnic group (England and Wales)

General Health by Age by sex by ethnic group (England and Wales)

HSE shows fairly strong association between ‘poor’ General Health and a ‘high’ GHQ12 score

Page 32: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Census to the rescue?

100% data allows measurement of health differences with…

the full 16 point ethnic classification the mixed the Chinese the Non-British whites

Detail on age including: 55-65; 66-75; 75+

Page 33: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

men: % ‘not good’ general health

0

5

10

15

20

25

30

35

40

45

50

0 to 15 16 to 24 25 to 34 35 to 54 55 to 59 60 to 64 65 to 74 75 andover

Irish Indian Pakistani Bangladeshi Black Caribbean Black African Chinese

Page 34: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

women: % ‘not good’ general health

0

5

10

15

20

25

30

35

40

45

50

0 to 15 16 to 24 25 to 34 35 to 54 55 to 59 60 to 64 65 to 74 75 and over

Irish Indian Pakistani Bangladeshi Black Caribbean Black African Chinese

Page 35: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

difference in % with ‘not good’ general health Indian v general population

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0 to 15 16 to 24 25 to 34 35 to 54 55 to 59 60 to 64 65 to 74 75 +

Page 36: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

difference in % with ‘not good’ general health Pakistani v general population

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30

0 to 15 16 to 24 25 to 34 35 to 54 55 to 59 60 to 64 65 to 74 75 +

Page 37: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

difference in % with ‘not good’ general health Bangladeshi v general population

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0

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10

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25

30

0 to 15 16 to 24 25 to 34 35 to 54 55 to 59 60 to 64 65 to 74 75 +

Page 38: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

difference in % with ‘not good’ general health Black Caribbean v general population

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0

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10

15

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25

30

0 to 15 16 to 24 25 to 34 35 to 54 55 to 59 60 to 64 65 to 74 75 +

Page 39: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

difference in % with ‘not good’ general health Black African v general population

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0

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15

20

25

30

0 to 15 16 to 24 25 to 34 35 to 54 55 to 59 60 to 64 65 to 74 75 +

Page 40: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

difference in % with ‘not good’ general health Chinese v general population

-10

-5

0

5

10

15

20

25

30

0 to 15 16 to 24 25 to 34 35 to 54 55 to 59 60 to 64 65 to 74 75 +

Page 41: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

difference in % with ‘not good’ general health Irish v general population

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5

10

15

20

25

30

0 to 15 16 to 24 25 to 34 35 to 54 55 to 59 60 to 64 65 to 74 75 +

Page 42: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Male : Female Ratio of proportion

with ‘not good’ general health

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

0 to 15 16 to 24 25 to 34 35 to 54 55 to 59 60 to 64 65 to 74 75 and over

General Irish Indian Pakistani Bangladeshi

male health worse

female health worse

Page 43: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Explaining ethnic differences?

Complex relationships - won’t get very far without micro-data - bring on SARs!

but a detailed description of patterns is a good starting point in research.

Extra detail revealed by Census is basis for more focussed questions

Page 44: Researching ethnic differences in health: finding the right data Mark Brown, CCSR CCSR Seminar Series: 2004.

Final thoughts on sample surveys the balance between variable detail and sample size

in the 1999 HSE and the 1994 NSEM seems wrong! We can never get near to the potential promised by the variables

effect of inadequate sample size is that theory underpinning research questions is sacrificed in the pursuit of statistical significance?

But a statistically significant finding may not be interesting or valid.

Just because a finding lacks statistical significance doesn’t make it invalid.