1. Main facts and figures

  • in 2014, there were no meaningful differences between ethnic groups in the percentage of people aged 16 and over who screened positive for probable post-traumatic stress disorder (PTSD) in the month before they were surveyed
  • although the table shows differences between groups, sample sizes were too small to draw reliable conclusions about these results
Things you need to know

A positive screen for post-traumatic stress disorder (PTSD) indicates that someone is likely to have PTSD, based on symptoms they have described. A full clinical assessment would be needed for diagnosis. The questions in the Adult Psychiatric Morbidity Survey (APMS) are used to estimate how common PTSD is likely to be in the adult population, but they aren’t used as part of any national screening programme in England.

The survey covers people aged 16 or older who live in private households. It doesn’t include those who live in institutional settings (such as hospitals or prisons) or in temporary housing (such as hostels or bed and breakfasts) or those who sleep rough. People living in such settings are likely to have worse mental health than those living in private households. There were 7,546 respondents to the survey.

These statistics have been age-standardised so comparisons can be made between ethnic groups as if they had the same age profile (an age profile shows the number of people of different ages within an ethnic group). The statistics do not tell you the actual percentage of people in each ethnic group who would screen positive for PTSD.

Keep in mind when making comparisons between ethnic groups that all survey estimates are subject to a degree of uncertainty as they are based on a sample of the population. The degree of uncertainty is greater when the number of respondents is small, so it will be highest for minority ethnic groups. In this situation, the number of respondents in each group was too small to make any conclusions about differences between the groups.

These statistics are based on participants’ direct responses (as opposed to someone else filling in the survey). As a result, socially undesirable or stigmatised feelings and behaviours may be under-reported. This is a risk with any survey based on self-reported data.

The ethnic groupings used here are broad and there is no breakdown of data for the more specific subgroups each contains. Some of these subgroups have very different experiences to one another. For example, the Black/Black British group could include both recent migrants from Somalia and Black people born in Britain to British parents.

What the data measures

This data measures the percentage of people aged 16 or older in different broad ethnic groups who screened positive for probable post-traumatic stress disorder (PTSD) in the month prior to being surveyed. The data source is the Adult Psychiatric Morbidity Survey (APMS) that was conducted in private households across England in 2014.

Post-traumatic stress disorder (PTSD) is an anxiety disorder caused by very stressful, frightening or distressing events. Someone with PTSD often relives the traumatic event through nightmares and flashbacks, and may experience feelings of isolation, irritability and guilt. They may also find sleeping and concentrating difficult. These symptoms are often severe and persistent enough to have a significant impact on the person’s day-to-day life.

The ethnic categories used in this data

For this data, the number of people surveyed (the ‘sample size’) was too small to draw any firm conclusions about specific ethnic categories. Therefore, the data is broken down into the following broad groups, based on the ONS-harmonised ethnic group questions for use on national surveys.

  • Asian/Asian British
  • Black/Black British
  • Mixed/Multiple and Other
  • White British
  • White Other

2. By ethnicity and sex

Percentage of people aged 16 years and over who screened positive for PTSD in the month prior to the survey by ethnicity and sex
Ethnicity All Men Women
Asian 5.8 6.1 5.3
Black 8.3 5.1 10.9
Mixed/Other 5.8 5.4 6.2
White - British 4.2 3.5 4.9
White - Other 2.2 1.8 2.5

Download table data (CSV) Source data (CSV)

Summary

This data shows that:

  • there were no meaningful differences between ethnic groups or between sexes in the proportion of adults screening positive for probable post-traumatic stress disorder (PTSD) in the month prior to the survey
  • differences between groups and between sexes were observed but they cannot be relied upon, most probably because of the small sample sizes involved

3. Methodology

Interviewers for the APMS asked questions using the PTSD Checklist – Civilian (PCL-C), a 17-item questionnaire based on the Diagnostic Statistical Manual (DSM-IV) symptoms of post-traumatic stress disorder (PTSD).

Each survey involved interviewing a large stratified probability sample of the general population, covering people living in private households. The full adult age range was covered, with the youngest participants aged 16 and the oldest over 100.

While a positive screen for PTSD isn’t a diagnosis, it does suggest the person probably has PTSD and warrants a clinical assessment. The ‘Methods’ chapter of the Adult Psychiatric Morbidity Survey 2014 (PDF) sets out the specific methodology of the PCL-C.

The prevalence of PTSD is determined here by dividing the number of respondents with a score of 50 or more on the PCL-C by the total number of respondents.

The resulting statistics for PTSD have been age-standardised. This is because the prevalence of common mental disorders is related to age and the age profile can differ considerably between ethnic groups. (An age profile shows the number of people of different ages within an ethnic group.) This adjustment allows comparisons to be made between ethnic groups as if they had the same age profile.

The survey covers people who live in private households. It doesn’t include those who live in institutional settings (such as hospitals or prisons) or in temporary housing (such as hostels or bed and breakfasts) or those who sleep rough. People living in such settings are likely to have worse mental health than those living in private households (Gill et al. 1996; cited in APMS 2014).

Where a selected participant could not take part in a long interview due to a physical or mental health condition, some information about this was recorded by the interviewer on the doorstep. This information may be biased due to it having been collected from another household member.

Socially undesirable or stigmatised feelings and behaviours may be underreported. While this is a risk for any study based on self-report data, the study goes some way to minimising this by collecting particularly sensitive information in a self-completion format.

Some people selected for the survey could not be contacted or refused to take part. The achieved response rate (57%) is in line with that of similar surveys (Barnes et al. 2010; cited in APMS 2014). Weighting helps take account of those who were selected for the survey but didn’t take part.

Weighting

Statisticians rebalance or ‘weight’ the survey results to more accurately represent the general population. This helps to make them more reliable. Survey weights are usually applied to make sure the survey sample has broadly the same sex, age, ethnic and geographic make up as the general population.

Biases in sample selection for the phase 1 interviews were addressed through weighting so that the results were representative of the English household population aged 16 and over. Weights for phase 2, the follow-up of some respondents, were calculated through a process of modelling the probability of being selected and responding, then relating the result to the phase 1 weighting figure.

Confidence intervals

Confidence intervals for each ethnic group are available in the ‘download the data’ section.

Based on survey results, it’s estimated that 4.9% of White British women screened positive for probable PTSD.

This estimate is based on a random sample of adults rather than the whole population of England. The measure makes an estimate of the percentage of different groups who would screen positive for probable PTSD, but it’s impossible to be 100% certain of the true percentage.

It’s 95% certain, however, that somewhere between 4.1% and 5.9% of all White British women in England would have screened positively for probable PTSD. In statistical terms, this is a 95% confidence interval. This means that if 100 random samples were taken, then 95 times out of 100 the estimate would fall between the lower and upper bounds of the confidence interval. But 5 times out of 100 it would fall outside this range.

The smaller the survey sample, the more uncertain the estimate and the wider the confidence interval. For example, fewer Black/Black British women responded to the survey than White British women, so we can be less certain about the estimate for the smaller group. This greater uncertainty is expressed by a wider confidence interval, for example of between 5.6% and 20.3% for Black/Black British women.

All the differences noted in the text are statistically significant. The statistical significance of differences are approximate because they are determined where the 95% confidence intervals for 2 groups or time periods don't overlap.

An example of non-overlapping confidence intervals would be the results for White British men, which had a confidence interval of between 2.7% and 4.5%, and the results for Black women, which had a confidence interval of between 5.6% and 20.3%.

Suppression rules and disclosure control

Risk to disclosure has been accounted for with limitations of the level of disaggregation, size of category groupings, and the maintaining of large underlying populations for each level. No further suppression or other disclosure control has been applied.

Rounding

Percentages have been rounded to one decimal point.

Related publications

Full references for other sources cited in this commentary can be found in the report this information has been sourced from Adult Psychiatric Morbidity Survey: Survey of Mental Health and Wellbeing, England, 2014.

Adult Psychiatric Morbidity Survey 2007

Publications using APMS data (PDF)

Quality and methodology information

4. Data sources

Source

Type of data

Survey data

Type of statistic

National Statistics

Publisher

NHS Digital

Publication frequency

Every 7 years (further publications dependent on further surveys being commissioned)

Purpose of data source

The Adult Psychiatric Morbidity Survey (APMS) series shows the proportion of adults in England who have or exhibit symptoms of mental illness and/or are receiving treatment for mental illness. It doesn’t include the homeless or people in hostels, hospitals, prisons or other institutional settings.

5. Download the data

APMS_adults_with_PTSD - Spreadsheet (csv) 5 KB

This file contains the following: ethnicity, sex, value, confidence intervals and sample size