Post-traumatic stress disorder in Canada: Technical notes

On this page

• Data source
• Target population
• Sampling
• Weighting
• Release rules for estimated proportions
• Variables
  • Post-traumatic stress disorder (PTSD) measures
  • Traumatic events
  • Sociodemographic characteristics
  • Health, mental health, and well-being
  • Use of mental health care and barriers to care
• Glossary of key terms
• References

Data source

Data used in this data tool came from the Survey on Mental Health and Stressful Events (SMHSE)^{Footnote 1}, a national survey focused on PTSD and traumatic events developed by the Public Health Agency of Canada (PHAC) and Statistics Canada that aims to understand how stressful events can impact a person’s mental health and well-being. Data were collected from August to December 2021 (cycle 1) and from September to December 2023 (cycle 2).

Target population

The target population for the SMHSE was people in Canada aged 18 years and older, living in the 10 provinces. People living in the three territories were excluded, as were people living on reserves, people living in institutions, and people living in collective dwellings.

Sampling

The SMHSE is a cross-sectional survey that used a two-stage design, with dwelling as the initial sampling unit and person as the subsequent sampling unit. The sampling frame was stratified by province, with a random sample of dwellings within each province. The initial sample was 35,000 dwellings. There were a total of 16,114 respondents to the survey and 12,577 agreed to share their responses with PHAC.

Weighting

To ensure the findings were representative of the population in the 10 provinces and properly adjusted for nonresponse, survey weights provided by Statistics Canada were applied to the calculation of all proportions. To account for the effects of the complex survey design of the SMHSE, the 95% confidence intervals (CIs) for all proportions were estimated using bootstrap (i.e., replicate) weights provided by Statistics Canada. All analyses were performed with SAS Enterprise Guide version 9.4 (SAS Institute Inc., Cary, NC, US).

Release rules for estimated proportions

X

Suppressed to meet the confidentiality requirements of the Statistics Act.

E

Use with caution.

F

Too unreliable to be published.

Variables

PTSD measures

PTSD positive screen

Screening positive for PTSD is defined as scoring higher than 32 (out of 80) on the PTSD Checklist for DSM-5 (PCL-5) in the past month^{Footnote 2}, indicating moderate to severe symptoms of PTSD. Although a diagnosis of PTSD requires a trained and licensed clinician, a validated screening tool such as the PCL-5 can identify individuals who may have PTSD but would need further assessment to confirm a diagnosis.

PTSD current diagnosis

Respondents were asked about conditions, including PTSD, that had been diagnosed by a health professional that had already lasted, or were expected to last, 6 months or more. Respondents were considered to have a current diagnosis of PTSD if they answered yes to “Do you have post-traumatic stress disorder?”.

PTSD lifetime diagnosis

Respondents were asked about conditions, including PTSD, that had been diagnosed by a health professional that had already lasted, or were expected to last, 6 months or more. Respondents were considered to have a lifetime diagnosis of PTSD if they answered yes either to “Do you have post-traumatic stress disorder” or “Have you ever been diagnosed with post-traumatic stress disorder?”.

Traumatic events

Types of traumatic events experienced

Respondents were told: "Throughout life, sometimes things happen to people that are unusually or especially frightening, stressful or traumatic. Examples include experiencing sudden loss of someone close, witnessing or experiencing actual or threatened serious injury or illness, a serious accident or fire, exposure to violence, etc". Respondents were then asked: "Have you ever experienced any of the following highly stressful or traumatic events during your life?”. Respondents were told: “Include events that happened directly to you, events that you witnessed, events that you learned about that happened to a close family member or a close friend, and events that you were repeatedly exposed to details about it as part of your job”, and “Be sure to consider your entire life (growing up as well as adulthood) as you go through the list of events”. Respondents were then shown a list of types of traumatic events from a modified version of the Life Events Checklist for DSM-5 (LEC-5)^{Footnote 3} and instructed to select all that apply. Respondents who selected one or more event type were also asked: “What was the worst event that you experienced?”.

How worst event was experienced

Respondents who identified a worst event were asked: “How did you experience this event?” and were told to select all that apply. For the response option “I was repeatedly exposed to details about it as part of my job”, the following examples were given: “paramedic, police, military, or other first responder”.

Domains of life affected by worst event

Respondents who identified a worst event were asked: “In the past 12 months, have problems related to your worst event affected any of the following aspects of your life?”. Respondents were instructed to select all that apply.

Worst event was occupation-related

Respondents who identified a worst event were asked: “Was your worst event related to something that happened while you were at work?”.

Original response options were:

• Yes, related to current occupation
• Yes, related to past occupation
• No

For this product, the first two options (current and past occupation) were grouped together.

Worst event was related to the COVID-19 pandemic

Respondents who identified a worst event were asked: “Was the worst event that you have ever experienced related to the COVID-19 pandemic? (e.g., death of someone close to you from COVID-19, major stressful life changes due to COVID-19, etc)”.

Number of traumatic event types experienced

For respondents who selected one or more event type, a total number of traumatic event types was calculated categorized into: one, two, three, and four or more.

Sociodemographic characteristics

Age group

Respondents were asked: “What is your age?”. Raw age in years was re-categorized for this product. Age groups were approved by Statistics Canada and correspond to survey weights used to ensure representativeness of the sample.

Gender

Respondents were asked: “What is your gender?”. Respondents were told that “gender refers to current gender which may be different from sex assigned at birth and may be different from what is indicated on legal documents”. Response options included “male”, “female”, and “other”. However, the labels “men” and “women” are used in this product as they more closely align with gender. Those who reported another gender identity were excluded from analyses for confidentiality reasons.

Area of residence

Respondents provided their postal code, which was used to determine their geographic region. Statistics Canada uses postal codes to determine whether the respondent lives in a “population centre” (i.e., urban area) or a rural area. According to Statistics Canada, a population centre “has a population of at least 1,000 and a population density of 400 persons or more per square kilometre, based on population counts from the current Census of Population. All areas outside population centres are classified as rural areas”^{Footnote 4}.

Employment status (Cycle 1 only)

Respondents were asked about employment status the week before the survey. They were asked: “During that week, did you work at a job or business?”. Respondents were instructed to select “Yes” if they worked at least one hour “for pay (wages, salary, etc.)” or “in self-employment”, and instructed to select “No” if they “were away from work for the entire week for a reason such as vacation, illness, work schedule or layoff” or “did not have a job or business”. Respondents were then asked: “During that week, did you have a job or business from which you were absent?”. They were instructed to select “Yes” if they “were away from work for the entire week for a reason such as vacation, illness, parental leave or work schedule” or “were self-employed with a business, but no work was available”, and instructed to select “No” if they “did not have a job or business” or if they “had a casual job, but no work was available”.

Geographic region

Respondents were asked to provide their postal code in order to determine their geographic region. Due to small numbers in some regions, Newfoundland and Labrador, Prince Edward Island, Nova Scotia, and New Brunswick were grouped into “Atlantic Provinces”. The SMHSE did not include individuals living in the three territories.

Highlest level of education

Respondents were asked: “What is the highest certificate, diploma or degree that you have completed?”.

Household income

Respondents were asked: “What is your best estimate of your total household income received by all household members, from all sources, before taxes and deductions, during the year ending December 31, 2020/2022?” [the year in the question was 2020 for cycle 1 and 2022 for cycle 2]. Respondents were told "Income can come from various sources such as from work, investments, pensions or government. Examples include: Employment Insurance, social assistance, child benefits and otherincome such as child support, spousal support (alimony) and rental income". For this product, total household income was divided into tertiles (i.e., falling below the 33rd percentile, between the 33rd and the 67th percentile, and above the 67th percentile).

Immigration status

Respondents were asked the following questions: “Where were you born?”, “Are you a Canadian citizen?", and “Are you a landed immigrant or permanent resident?”. Non-immigrants included Canadian citizens by birth or by naturalization. Landed immigrants or permanent residents were defined as “a person who has been granted the right to live in Canada permanently by immigration authorities”. Other respondents were non-permanent residents including persons from another country who have a work or study permit or who are refugee claimants, and their family members sharing the same permit and living in Canada with them. For this product, landed immigrants, permanent residents, and non-permanent residents were grouped together as “immigrant”.

Marital status

Respondents were asked: “What is your marital status?”.

Original response options were:

1. Married (for Quebec residents only, respondents were instructed to select "Married" category if their marital status was “civil union”)
2. Living common law (definition provided: “Two people who live together as a couple but who are not legally married to each other”)
3. Never married (not living common law)
4. Separated (not living common law)
5. Divorced (not living common law)
6. Widowed (not living common law)

Racialized background

Respondents were asked to report if they identify to one or more of the following groups: White, South Asian (e.g., East Indian, Pakistani, Sri Lankan), Chinese, Black, Filipino, Arab, Latin American, Southeast Asian (e.g.,Vietnamese, Cambodian, Laotian, Thai), West Asian (e.g., Iranian, Afghan), Korean, Japanese, and Other. Respondents were categorized as being from a racialized background if they responded “yes” to any category other than “White”.

High-risk occupation (current and ever) (Cycle 2 only)

Respondents were asked: “Have you ever been a member of the Canadian Armed Forces, a public safety worker, or a healthcare professional?”. Respondents were told to select all that apply or to select “No” if none of the three options applied. Those who did not answer “No” to the question above were then asked: “Are you currently a member of the Canadian Armed Forces, a public safety worker, or a healthcare professional?”. Respondents were told to select all that apply or to select “No” if none of the three options applied.

Health, mental health, and well-being

Activities being done to maintain or improve health

Respondents were asked: “Are you currently doing any of the following activities to maintain or improve your health?”, and were instructed to select all that apply.

General health

Respondents were asked: “In general, how is your health?”. Original response options were: “poor”, “fair”, “good”, “very good”, and “excellent”.

General mental health

Respondents were asked: “In general, how is your mental health?”. Original response options were: “poor”, “fair”, “good”, “very good”, and “excellent”.

Current diagnosis of a mood and/or anxiety disorder

Respondents were asked about conditions that had been diagnosed by a health professional that had already lasted, or were expected to last, 6 months or more. Respondents were considered to have a current diagnosis of a mood disorder if they answered “yes” to: “Do you have a mood disorder such as depression, bipolar disorder, mania or dysthymia?” (Respondents were instructed to “Include manic depression”). Respondents were considered to have a current diagnosis of an anxiety disorder if they answered “yes” to: “Do you have an anxiety disorder such as a phobia, obsessive compulsive disorder or a panic disorder?”.

Screening positive for major depressive disorder

In the SMHSE, screening positive for major depressive disorder (MDD) means scoring ≥ 3 (out of 6) on the 2-item version of the Patient Health Questionnaire (PHQ-2)^{Footnote 5}, representing moderate to severe symptoms of MDD.

Screening positive for generalized anxiety disorder

In the SMHSE, screening positive for generalized anxiety disorder (GAD) means scoring ≥ 3 (out of 6) on the 2-item version of the Generalized Anxiety Disorder Scale (GAD-2)^{Footnote 6}, representing moderate to severe symptoms of GAD.

Frequency of cannabis use in the past month

Respondents were asked: “In the past 30 days, how often did you use cannabis?”. Respondents were told to “include marijuana or herb (i.e., dried flower or leaf), hashish or kief, cannabis oil, cannabis cartridges or disposable vape pens, liquid concentrate (e.g., hash oil, butane honey oil), solid concentrate (e.g., shatter, budder, wax), edibles (i.e., prepared food products), liquid (e.g., in cola, tea). Include both medical use and non-medical use of cannabis”. For this product, “not in the past month” includes those who reported never using cannabis as well as those who used previously but not in the past month.

Medical and non-medical cannabis use

Respondents who reported having used cannabis in the past 30 days were asked: “What is the main reason you use cannabis?”.

Frequency of heavy drinking in the past month

Respondents were asked: “During the past 30 days, did you have a drink of beer, wine, liquor or any other alcoholic beverage?”. Respondents were told to “include beer or coolers (bottle, can, or draft), wine or liquor or spirit (straight or mixed), including light beer”, and to exclude “de-alcoholised beer or coolers (0.5% alcohol) or non-alcoholic drinks, such as Virgin Mary or Shirley Temple”. Heavy drinking was defined as 4 or more drinks for women or 5 or more drinks for men, in one sitting. This was based on Canadian national low-risk drinking guidelines. Frequency of heavy drinking was determined by asking respondents who reported having one or more drinks in the past 30 days: “during the past 30 days, how often have you had [4 for women; 5 for men] or more drinks on one occasion?”.

Has ever seriously contemplated suicide

Respondents were asked: “Have you ever seriously contemplated suicide?”. Those who said “yes” were asked: “Have you ever seriously contemplated suicide as a result of the worst event that you have ever experienced?”. Here, the "worst event" refers to the traumatic event type that was identified as the worst the respondent experienced.

Social support

A mean score of 3 or higher across the 10 items of the Social Provisions Scale (SPS)^{Footnote 7} was considered to indicate high social support. On each item, a rating of 3 or 4 on a scale of 1 to 4 represents response categories of “strongly agree” or “agree”.

Applied for or received disability benefits (Cycle 2 only)

Respondents who were younger than 76 years were asked: “In the past three months, did you apply for or receive short-term or long-term disability benefits?”.

Applied for or received employment insurance benefits (Cycle 2 only)

Respondents who were younger than 76 years were asked: “In the past three months, did you apply for or receive employment insurance benefits?”.

Health-related reduction of work hours (Cycle 2 only)

Respondents who reported working in the past 3 months were asked: “Have you reduced your planned work hours in the past three months because of your own physical, mental, or emotional health?”.

Impact of health on reduction of work activity (Cycle 2 only)

Respondents who reported working in the past 3 months were asked: “In the past three months, how much has your own physical, mental or emotional health reduced the amount or the kind of activity you can do at work?”.

Use of mental health care and barriers to care

Access to mental health resources - ever

Respondents were asked: “Have you ever accessed any resources (on the internet, via phone or in person) to help manage your emotions, mental health or use of alcohol or drugs?”.

Received help for mental health problems - past 12 months

Respondents were asked: “During the past 12 months, did you receive the following kinds of help because of problems with your emotions, mental health or use of alcohol or drugs?”.

Respondents were asked to select all that apply:

• Information about these problems, treatments or available services
• Medication
• Counselling, therapy, or help for problems with personal relationships
• None

For the third option, respondents were told to “include support groups such as Alcoholics Anonymous(AA), Narcotics Anonymous”.

Unmet need for mental health care - past 12 months

Respondents were asked: “During the past 12 months, was there ever a time when you felt that you needed help for problems with your emotions, mental health or use of alcohol or drugs, but you didn’t receive it?”.

Reasons for unmet mental healthcare need - past 12 months

Respondents were asked: “During the past 12 months, was there ever a time when you felt that you needed help for problems with your emotions, mental health or use of alcohol or drugs, but you didn’t receive it?”. Those who answered “Yes” were then asked: “Why didn’t you receive the help you needed (during the past 12 months)?”. Respondents were asked to select all that apply.

Received traumatic event-related care - past 12 months

Respondents were asked: “During the past 12 months, have you talked to any of the following people about problems related to your worst event?”. Here, the “worst event” refers to the traumatic event type that was identified as the worst the respondent experienced. Respondents were asked to select all that apply.

Number of visits with professionals for traumatic event-related care - past 12 months

Respondents were asked: “How many times did you talk to [HEALTH PROFESSIONAL] about problems related to your worst event?”. These visits were specifically for care related to the traumatic event respondents identified as the worst they experienced. For this product, raw numbers of visits were grouped into four categories based on the frequency distribution.

Scheduling problems for traumatic event-related care appointments - past 12 months

Respondents were asked: “Did you experience any of the following problems with the scheduling of your appointments?”. These problems related specifically with appointments for care related to the traumatic event respondents identified as the worst they experienced. Respondents were asked to select all that apply.

Barriers to traumatic event-related care - past 12 months

Respondents were asked: “Did you experience any other difficulties getting the health care service you needed?”. These difficulties (or barriers) were specifically for getting care related to the traumatic event respondents identified as the worst they experienced. Respondents were asked to select all that apply.

Glossary of key terms

Federal Framework on Post-traumatic Stress Disorder

The Federal Framework on Post-traumatic Stress Disorder^{Footnote 8} was a response to the Post-Traumatic Stress Disorder Act^{Footnote 9}, which became law on June 21, 2018. The Act stipulated that a national conference be convened for the purpose of developing a comprehensive federal framework, with a number of key priorities, one of which included the improvement of the tracking of PTSD in Canada. The SMHSE^{Footnote 1}, which provides estimates of the prevalence of PTSD in Canada, was developed in response to this priority. Following the Act, a complete review of the effectiveness of the Federal Framework was completed in June of 2025.

Post-traumatic stress disorder (PTSD)

Post-traumatic stress disorder (PTSD) is a mental disorder that may occur after exposure to psychological stress. It is a collection of feelings, behaviours and experiences that can result from a single specific, severe, potentially psychologically traumatic event, or from a series of such events (e.g. actual or threatened death, serious injury, or sexual violence). A PTSD diagnosis requires a trained and licensed clinician to assess a specific set of signs and symptoms. PTSD may be diagnosed if symptoms persist for more than 1 month and cause significant distress or impairment. This distress or impairment may be in social, occupational, or other important areas of functioning. Symptoms of PTSD include recurring memories of the event, avoiding any reminders of the event, having negative changes in thoughts or mood, and having heightened awareness or strong reactions (psychological arousal or reactivity)^{Footnote 10}.

Potentially psychologically traumatic event (PPTE)

Potentially psychologically traumatic events (PPTEs) are events that have the potential to cause PTSD and other trauma-related mental health conditions. Psychological trauma does not require a physical injury to be harmful. Typical examples of PPTEs include adverse childhood experiences, motor vehicle accidents, and sexual assault and other types of violence^{Footnote 10}. In this data exploration tool, PPTEs are referred to as “traumatic events” or “traumatic event types”.