In brief
This is a study protocol, not a results paper, for a cluster randomised controlled trial testing a two-part community participatory intervention against usual care in two Chiangmai, Thailand subdistricts. It targets adults at high suicide risk, with suicidality symptoms as the primary outcome, and was designed...
What this article is about
Quick Answer
This is a study protocol, not a results paper, for a cluster randomised controlled trial testing a two-part community participatory intervention against usual care in two Chiangmai, Thailand subdistricts. It targets adults at high suicide risk, with suicidality symptoms as the primary outcome, and was designed because Thailand's earlier hospital-based depression care system expanded treatment access without lowering suicide mortality.
Student takeaways
Key Takeaways
- This is a study protocol, so no outcome results are reported yet; it describes the planned design of an ongoing cluster randomised controlled trial.
- Thailand's national hospital-based suicide surveillance and depression-care system (implemented from around 2010) raised depression care access from 5.1% (2009) to 48.5% (2016) but did not reduce the national suicide mortality rate, motivating this community-level trial.
- The trial randomises two Chiangmai Province districts (Mae Rim and Muang) at the subdistrict level, with one district assigned to the community participatory intervention and the other to control.
- The intervention combines a one-year, five-stage capacity-building process delivered by a 30-40 person subdistrict core team with a second year of community-led counselling, psychosocial support, economic assistance, and self-harm prevention activities.
- The researchers calculated a required sample of 235 participants per arm (inflated to 294 per arm, roughly 588 total, to allow for 20% dropout), with suicidality symptoms measured by an 8-question Thai screening tool (sensitivity 0.96, specificity 0.91) as the primary outcome.
Student summary
Why This Research Matters
Thailand has the highest suicide mortality rate in Southeast Asia, holding steady at about 8.0 per 100,000 people in 2019. That is striking because Thailand already built a national, hospital-based suicide prevention system, rolled out from around 2010, that dramatically expanded access to depression care, from 5.1% of people with depression receiving care in 2009 up to 48.5% by 2016. Despite that success inside the health system, the national suicide mortality rate did not budge. The research team behind this trial concluded that something outside the hospital walls was missing: sustained involvement from the community itself. This protocol describes a cluster randomised controlled trial designed to test whether a community-driven, participatory intervention can do what the hospital-based system alone could not.
The trial takes place in two districts of Chiangmai Province, Mae Rim and Muang, both chosen because they have high local suicide rates. Because the intervention works at the level of whole communities rather than individual patients, the researchers could not randomise person by person. Instead they randomised at the subdistrict (cluster) level: one district was assigned to receive the community participatory intervention, and the other served as the control. From each of the two districts, researchers picked one larger and one smaller subdistrict, giving two intervention subdistricts and two control subdistricts overall.
The intervention itself has two connected parts that unfold over roughly two years. The first is a one-year capacity-building process built around five stages of workshops: an introductory workshop that orients local stakeholders to the project; a community participatory data-collection and planning workshop where local people help identify who is at risk and why; a series of key competency training workshops that build practical skills; workshops that put the group's own designed interventions into action; and finally a lessons-learnt workshop that captures what worked. All of this is carried out by a subdistrict core team of roughly 30 to 40 people, drawn from subdistrict health centre staff, municipality personnel, community health volunteers, family caregivers, and local community leaders. The second part is a full year of community-led action: counselling, psychosocial support, help with financial hardship, and education aimed at preventing self-harm, all designed and carried out by the community itself rather than imposed from outside.
Participants eligible for the study are adults 18 years or older who have at least one marker of elevated suicide risk: a past suicide attempt, a chronic mental illness, a chronic non-communicable disease, or a significant life crisis such as job loss, serious debt, or bereavement. People with active psychotic symptoms, those too unwell to take part, those planning to move away, and non-Thai speakers are excluded. Participants are recruited through subdistrict health centres.
Using a statistical power of 0.9, a significance level of 0.05, and a small-to-medium expected effect size, the researchers calculated they need 235 participants per study arm; after accounting for an expected 20% dropout, they are recruiting 294 per arm, for roughly 588 participants across the whole trial.
The main outcome the trial is measuring is suicidality symptoms, using an eight-question Thai-language screening tool with reported sensitivity of 0.96 and specificity of 0.91. Secondary outcomes include depression symptoms (using the PHQ-2 and PHQ-9), quality of life (EQ-5D-5L), stress levels, and how easily people can access health and community services. Because this is a protocol paper, it describes the planned methods rather than final results; findings have not yet been reported.
For nursing students, this study is a clear illustration of a community-based, upstream approach to suicide prevention that complements clinic-based care rather than replacing it. It also models how community health workers, not just clinicians, can be trained and organised to identify at-risk neighbours and respond with practical, locally relevant support. Students appraising this protocol should note its strengths, a clear cluster design, a pre-registered trial number, and ethics approval, alongside its real constraints: only two intervention and two control subdistricts, which limits statistical power and raises the possibility that people or ideas could "spill over" between neighbouring intervention and control communities.
Source abstract
Study Overview
Introduction The age-standardised suicide mortality rate in Thailand has been stable at a high level in recent years, highlighting the need for suicide prevention interventions. In Thailand, community involvement plays a key role in health promotion. The aim of this ongoing trial is to evaluate the efficacy of a community participatory intervention in two subdistricts in Thailand for reducing suicidality symptoms among individuals considered at high risk for suicide and compare the outcomes to two control subdistricts.Methods and analysis In this cluster (subdistrict) randomised controlled trial, we randomised two districts to either the community participatory intervention arm or the control arm. From each district, we selected one large and one small subdistricts. We estimated that we need 235 participants per study arm, who were recruited from subdistrict health centres. The primary outcome is suicidality symptoms. Secondary outcomes are depression symptoms, quality of life, stress level and health and community service accessibility.Ethics and dissemination This trial has been approved by the Research Ethics Committee, Faculty of Nursing, Chiangmai University (number 050/2022). All participants were required to provide informed consent. The findings of the study will be disseminated in peer-reviewed journals and via conferences.Trial registration number TCTR20220620003; the Thai Clinical Trials Registry.
Evidence appraisal
Main Findings
- This is a study protocol, so no outcome results are reported yet; it describes the planned design of an ongoing cluster randomised controlled trial.
- Thailand's national hospital-based suicide surveillance and depression-care system (implemented from around 2010) raised depression care access from 5.1% (2009) to 48.5% (2016) but did not reduce the national suicide mortality rate, motivating this community-level trial.
- The trial randomises two Chiangmai Province districts (Mae Rim and Muang) at the subdistrict level, with one district assigned to the community participatory intervention and the other to control.
- The intervention combines a one-year, five-stage capacity-building process delivered by a 30-40 person subdistrict core team with a second year of community-led counselling, psychosocial support, economic assistance, and self-harm prevention activities.
- The researchers calculated a required sample of 235 participants per arm (inflated to 294 per arm, roughly 588 total, to allow for 20% dropout), with suicidality symptoms measured by an 8-question Thai screening tool (sensitivity 0.96, specificity 0.91) as the primary outcome.
Practice transfer
Clinical Relevance
- Nurses working in community and public health settings can consider participatory, community-led models as a complement to clinical depression care, since hospital-based care alone did not reduce Thailand's suicide mortality rate.
- Community health volunteers, caregivers, and local leaders can be trained as part of a structured, multi-stage capacity-building process to identify and support people at elevated suicide risk, extending the reach of formal mental health services.
- Screening for suicide risk in community settings can target people with known risk markers, such as a past suicide attempt, chronic mental illness, chronic non-communicable disease, or a recent major life crisis, rather than the general population.
- Brief, validated tools such as the 8-question suicidality screen and the PHQ-2/PHQ-9 can support routine identification of at-risk individuals in primary care and community health centres.
- Because this is a protocol without reported outcomes, nurses should treat the intervention as promising in design but not yet evidence-based in effect; practice change should wait for the trial's published results.
Faculty notes
Educational Relevance
This BMJ Open protocol paper, authored by Sornpaisarn, Rehm, Tamdee and colleagues from the Centre for Addiction and Mental Health (Toronto), Chiangmai University, and Thai community partners, describes an ongoing cluster randomised controlled trial testing a community participatory suicide-prevention intervention in Chiangmai Province, Thailand. It is a useful teaching case for research appraisal because it is transparent about design tradeoffs typical of community-level (as opposed to individual-level) trials.
The rationale is compelling for discussion: Thailand implemented a national hospital-based suicide surveillance and depression-care system from around 2010 that nearly tenfold-increased depression care access (from 5.1% in 2009 to 48.5% in 2016), yet national suicide mortality remained flat at roughly 8.0 per 100,000 (2019), the highest rate in the ASEAN (Southeast Asian) region. The investigators frame this as evidence that clinical-system improvements alone are insufficient without corresponding community-level engagement, a useful prompt for discussing the social determinants of suicide risk and the limits of hospital-centred prevention models.
Methodologically, the trial randomises at the subdistrict (cluster) level rather than the individual level, a common and necessary design choice when an intervention is inherently delivered to a whole community rather than to individual patients. Two districts (Mae Rim and Muang) selected for high suicide rates were each assigned wholesale to intervention or control, with one large and one small subdistrict sampled from each, yielding two intervention and two control clusters. This is a small number of clusters, and the authors explicitly flag the risk of contamination or "spillover effects" between neighbouring communities, along with the limited statistical power inherent to so few clusters, a good springboard for discussing the tradeoffs of cluster RCTs versus individually randomised designs.
The intervention combines a one-year, five-stage capacity-building process (introductory workshops, participatory data collection and planning, competency training, implementation of community-designed interventions, and a lessons-learnt phase) delivered by a 30-to-40-person subdistrict core team of health centre staff, municipal personnel, volunteers, caregivers, and community leaders, followed by a second year of community-led action including counselling, psychosocial and economic support, and self-harm prevention education. This bottom-up, capacity-building structure is worth contrasting with top-down, expert-delivered prevention programs when teaching intervention design.
Sample size was calculated with reasonable rigour (power 0.9, alpha 0.05, small-to-medium effect size of 0.3) yielding 235 participants needed per arm, inflated to 294 per arm (588 total) to allow for 20% attrition. Eligible participants are adults with documented risk markers, prior suicide attempt, chronic mental illness, chronic non-communicable disease, or major life crisis, recruited through subdistrict health centres; people with active psychosis, inability to participate, imminent relocation, or non-Thai language are excluded.
The primary outcome, suicidality symptoms via an 8-question Thai screening instrument (sensitivity 0.96, specificity 0.91), is well validated for local use; secondary outcomes (PHQ-2/PHQ-9 depression, EQ-5D-5L quality of life, a stress scale, and service accessibility) are internationally recognised and support cross-study comparison. Analysis of covariance is planned for the primary comparison, supplemented by thematic analysis of qualitative community data.
Ethically, the study received approval from the Research Ethics Committee, Faculty of Nursing, Chiangmai University (050/2022), is prospectively registered (TCTR20220620003), and requires written informed consent; the authors note patients and the public were not involved in designing the study itself, a limitation worth flagging given the intervention's participatory framing. As a protocol, no outcome data are yet reported. For seminar discussion, this paper works well alongside completed community-based suicide prevention trials to compare design choices and to discuss how nurses might translate a "capacity-building" model into Canadian community health settings.
Critical appraisal
Limitations
- As a protocol paper, the trial has not yet reported outcome data, so efficacy claims cannot be made until results are published.
- Only two intervention subdistricts and two control subdistricts are included, a small number of clusters that limits statistical power and the precision of the estimated intervention effect.
- The small number of clusters raises the risk of spillover or contamination effects between neighbouring intervention and control communities, which the authors themselves acknowledge.
Classroom use
Discussion Questions
- Why might a hospital-based depression care system succeed at increasing treatment access while failing to reduce national suicide mortality, and what does that suggest about the social determinants of suicide risk?
- What are the advantages and disadvantages of randomising by subdistrict (cluster) rather than by individual participant in a community-level suicide prevention trial like this one?
- How might having only two intervention and two control subdistricts affect the trial's statistical power and the confidence we can place in its eventual findings?
- What is meant by 'spillover' or contamination between neighbouring communities in a cluster trial, and how could it bias the results of this particular study?
- How does the five-stage capacity-building process described in this protocol (introduction, data collection/planning, competency training, implementation, lessons learnt) compare to how mental health programs are typically rolled out in your own practice setting?
- What role do community health volunteers, caregivers, and local leaders play in this intervention, and how does that differ from a clinician-led suicide prevention program?
- Why did the researchers choose an 8-question Thai screening tool with reported sensitivity of 0.96 and specificity of 0.91 as their primary outcome measure, and what do those numbers mean in practice?
- The inclusion criteria target people with a past suicide attempt, chronic mental illness, chronic non-communicable disease, or a major life crisis. Do you think this is the right at-risk population to focus a community intervention on? Why or why not?
- The authors note that patients and the public were not involved in designing this study, despite it being a 'community participatory' intervention. Is this a contradiction, and how might future trials address it?
- How could a similar capacity-building and community participatory model be adapted for suicide prevention in a Canadian rural or Indigenous community context, given differences in health systems and culture?
Knowledge check
Quiz
1. What type of publication is this article?
- A completed randomised controlled trial reporting final results
- A study protocol describing an ongoing cluster randomised controlled trial
- A systematic review of suicide prevention interventions
- A case report of a single suicide attempt survivor
Rationale: The abstract describes this as a trial protocol: 'The aim of this ongoing trial is to evaluate the efficacy of a community participatory intervention... Methods and analysis...'
2. What motivated the researchers to design this community-level trial, according to the background described in the full text?
- Thailand had no prior suicide prevention programs of any kind
- A national hospital-based system increased depression care access but suicide mortality remained unchanged
- Suicide rates in Thailand had recently doubled
- The government mandated a new community health policy
Rationale: The full text explains that Thailand's hospital-oriented system (implemented from around 2010) raised depression care access from 5.1% (2009) to 48.5% (2016), yet the national suicide mortality rate stayed the same, prompting a community-focused approach.
3. At what level does randomisation occur in this trial?
- Individual participant level
- Hospital ward level
- Subdistrict (cluster) level
- Provincial level
Rationale: The abstract states this is 'a cluster (subdistrict) randomised controlled trial' in which 'two districts' were 'randomised... to either the community participatory intervention arm or the control arm.'
4. How many participants per study arm did the researchers estimate they needed, according to the abstract?
- 100 participants per arm
- 150 participants per arm
- 235 participants per arm
- 500 participants per arm
Rationale: The abstract states: 'We estimated that we need 235 participants per study arm, who were recruited from subdistrict health centres.'
5. What is the primary outcome measured in this trial?
- Quality of life
- Suicidality symptoms
- Stress level
- Health service accessibility
Rationale: The abstract states: 'The primary outcome is suicidality symptoms.' Depression, quality of life, stress, and service accessibility are listed as secondary outcomes.
6. Which of the following is included as a secondary outcome in this trial?
- Blood pressure control
- Medication adherence
- Depression symptoms
- Hospital readmission rate
Rationale: The abstract lists secondary outcomes as 'depression symptoms, quality of life, stress level and health and community service accessibility.'
7. Which two districts in Chiangmai Province were selected for this trial, based on the full text?
- Mae Rim and Muang
- Chiang Dao and San Sai
- Doi Saket and Hang Dong
- Mae Taeng and Saraphi
Rationale: The full text of the protocol identifies the two selected districts, chosen for their high local suicide rates, as Mae Rim and Muang.
8. Approximately how many people make up the subdistrict core team that delivers the intervention's capacity-building process?
- 5-10 people
- 10-15 people
- 30-40 people
- 100-150 people
Rationale: According to the full text, the intervention is delivered by a subdistrict core team of roughly 30 to 40 people, including health centre staff, municipality personnel, volunteers, caregivers, and community leaders.
9. Which body approved the ethics of this study, and what is the approval number?
- Health Canada, HC-2022-050
- Research Ethics Committee, Faculty of Nursing, Chiangmai University, number 050/2022
- World Health Organization, WHO-2022-066
- Thai Ministry of Public Health, MOPH-2022
Rationale: The abstract states: 'This trial has been approved by the Research Ethics Committee, Faculty of Nursing, Chiangmai University (number 050/2022).'
10. What limitation do the authors themselves acknowledge about the trial's design?
- The intervention was too expensive to implement
- The small number of subdistricts (two intervention, two control) and the potential for spillover effects
- The primary outcome tool has never been validated
- Participants were not given informed consent
Rationale: The full text notes the study acknowledges 'the small number of subdistricts with only two interventions and two control subdistricts and any potential spillover effects.'
Study cards
Flashcards
What is the overall aim of this trial?
To evaluate the efficacy of a community participatory intervention, delivered in two subdistricts in Thailand, for reducing suicidality symptoms among people at high risk of suicide, compared with two control subdistricts.
What is Thailand's suicide mortality rate, and how does it compare regionally?
About 8.0 per 100,000 population in 2019, the highest age-standardised suicide mortality rate in Southeast Asia.
What earlier national program is described as the background to this trial?
A hospital-oriented suicide surveillance and depression-care system implemented in Thailand from around 2010.
What effect did that earlier hospital-based system have on depression care access and suicide mortality?
It increased depression care access from 5.1% (2009) to 48.5% (2016) of people with depression, but the national suicide mortality rate remained unchanged.
What type of study design is used in this trial?
A cluster (subdistrict) randomised controlled trial.
Which two districts of Chiangmai Province were selected for the trial?
Mae Rim and Muang, both chosen for their high local suicide rates.
How were subdistricts selected within each district?
One large and one small subdistrict were selected from each of the two districts.
How many participants per arm were estimated to be needed, and how many after accounting for dropout?
235 participants per arm were estimated as needed; after allowing for 20% dropout, 294 per arm (about 588 total) are being recruited.
What statistical parameters were used in the sample size calculation?
A power of 0.9, an alpha of 0.05, and a small-to-medium expected effect size of 0.3.
What is the primary outcome of this trial?
Suicidality symptoms, measured with an 8-question Thai assessment tool with reported sensitivity of 0.96 and specificity of 0.91.
Name the four secondary outcomes described in the abstract.
Depression symptoms, quality of life, stress level, and health and community service accessibility.
What are the two parts of the community participatory intervention?
Part 1 is a one-year, five-stage capacity-building process; Part 2 is a year of community-led participatory suicide prevention actions.
List the five stages of the capacity-building process.
Introductory workshops, community participatory data collection and planning workshops, key competency training workshops, implementation of designed intervention workshops, and lessons-learnt summary workshops.
Who makes up the subdistrict core team delivering the intervention?
About 30-40 people, including health centre officials, municipality personnel, community health volunteers, caregivers, and community leaders.
What kinds of activities happen during the community action year of the intervention?
Counselling, psychosocial support, economic assistance, and self-harm prevention education, designed and delivered by the community itself.
Who is eligible to participate in this trial?
Adults 18 or older with a past suicide attempt, chronic mental illness, chronic non-communicable disease, or a significant life crisis such as job loss, debt, or bereavement.
Who is excluded from participating in this trial?
People with active psychotic symptoms, those unable to participate due to illness, those planning to move away, and non-Thai speakers.
Which committee approved the ethics of this study, and what is the approval number?
The Research Ethics Committee, Faculty of Nursing, Chiangmai University, approval number 050/2022.
What is the trial registration number and registry?
TCTR20220620003, registered with the Thai Clinical Trials Registry.
What limitation regarding cluster numbers do the authors acknowledge?
The small number of subdistricts (only two intervention, two control), which limits statistical power and raises the possibility of spillover effects between neighbouring communities.
Search-ready answers
Frequently asked questions
Has this trial already reported its results?
No. This is a study protocol describing the planned design of an ongoing cluster randomised controlled trial; efficacy results have not yet been published.
What is a community participatory intervention for suicide prevention?
In this trial, it is a two-part program combining a one-year capacity-building process (workshops on data collection, planning, and skills training) with a year of community-designed and community-delivered actions such as counselling, psychosocial support, economic assistance, and self-harm prevention education.
Why did researchers focus on community-level intervention instead of expanding hospital-based care further?
Because Thailand's earlier hospital-oriented depression care system (implemented from around 2010) substantially increased treatment access (from 5.1% in 2009 to 48.5% by 2016) without reducing the national suicide mortality rate, suggesting community-level factors also need to be addressed.
How does a cluster randomised controlled trial differ from a standard individually randomised trial?
In a cluster trial, whole groups (here, subdistricts) are randomly assigned to intervention or control, rather than individual participants, because the intervention is delivered at the community level rather than to single patients.
How many people are being recruited into this trial?
The researchers calculated a need for 235 participants per arm, and are recruiting 294 per arm (about 588 total) to allow for an expected 20% dropout.
Who is eligible to take part in this trial?
Adults 18 years or older recruited from subdistrict health centres who have a past suicide attempt, a chronic mental illness, a chronic non-communicable disease, or a major life crisis such as job loss, debt, or bereavement.
What tool is used to measure the trial's main outcome?
An 8-question Thai suicidality assessment tool with reported sensitivity of 0.96 and specificity of 0.91.
Where is this trial taking place?
In two districts of Chiangmai Province, Thailand: Mae Rim and Muang, chosen for their high local suicide rates.
What are the main limitations of this trial's design?
The trial includes only two intervention and two control subdistricts, a small number of clusters that limits statistical power and creates a risk of spillover effects between neighbouring communities.
Was this study ethically approved and registered?
Yes. It was approved by the Research Ethics Committee, Faculty of Nursing, Chiangmai University (number 050/2022) and is prospectively registered with the Thai Clinical Trials Registry (TCTR20220620003).