The survey was commissioned by beyondblue, which is an Australian, non-government non-profit organization working to address issues associated with depression and anxiety disorders. The survey was conducted by Roy Morgan Research Ltd. in March 2017. The sample was drawn by a process of random digit dialing of both landlines and mobile telephones covering the whole of Australia. Up to six calls per number were made to establish contact. Interviewers ascertained whether there were residents in the household aged 18 or over and, if there were multiple, selected one for interview using the next-birthday method. Oral consent was obtained from all respondents before commencing the interviews. Computer-assisted telephone interviews were carried out with 3002 people. There are a number of ways to calculate survey response rates. For this survey, the American Association for Public Opinion Research response rate  was 3.1% and the simple response rate was 12.2%.
The survey interview covered sociodemographic characteristics, intentions and confidence to help a person in distress, barriers and enablers, actual helping behaviour, the participant’s own suicidal thoughts, help received, attitudes to suicide, exposure to suicide, training in suicide prevention and exposure to suicide prevention messages in the media. The full interview is given in Additional file 1. Only the measures of specific relevance to the aims of the present paper are described in detail below.
Participants were asked questions about sociodemographic characteristics, which were coded as follows for the analyses reported here: female gender, age group (18–30, 31–59, 60+), mainly speak a language other than English, education with Bachelor’s degree or above and non-urban location.
Helping intentions were assessed in relation to one of six vignettes of distressed persons that were randomly assigned to participants. The vignettes covered male or female versions of three scenarios: a person with distress and adverse life events, a person with distress and adverse life events but no overt suicidality (“John/Jenny says he/she feels he/she will never be happy again and believes his/her family would be better off without him/her”), and a person with distress and adverse life events with overt suicidality (“John/Jenny says he/she feels s/he will never be happy again and believes his/her family would be better off without him/her. You run into a friend of John’s/Jenny’s. S/he tells you that John/Jenny told him/her he/she feels desperate and has been thinking of ways to end his/her life”). The six scenarios are given in Additional file 1.
Participants were then asked “How likely is it that you would take the following actions with John/Jenny?” Very unlikely, Unlikely, Neither likely nor unlikely, Likely, Very likely. The actions presented were: “Ask about how he/she is feeling; Listen to John’s/Jenny’s problems without judgement; Remind him/her what he/she has going for himself/herself*; Ask how you can help; Try to solve John’s/Jenny’s problems*; Reassure John/Jenny that you know exactly how badly he/she feels*; Help make an appointment with a health professional – for example a GP or counsellor; Call a crisis line – for example, Lifeline; Go to an appointment with a professional with him/her – for example a GP; Ask if he/she has been thinking about killing himself/herself; If John/Jenny told me he/she was thinking about killing himself/herself, I would try to make him/her understand that suicide is wrong*; If John/Jenny told me he/she was thinking about killing himself/herself, I would ask if he/she has a means to kill herself/himself – for example, pills or a weapon; If John/Jenny told me he/she was thinking about killing himself/herself, I would listen to why he/she wants to die; I would tell him/her how much it will hurt his/her family and friends if he/she were to kill himself/herself*; I would ask if he/she has a plan for suicide – for example a date or how they will die”.
Ten of the items above are recommended by expert-consensus guidelines, while 5 are recommended against (the latter are asterisked above) . The 10 recommended items were made into a Positive Intentions scale by averaging the ratings across items to give a score range from 1 (every item rated ‘very unlikely’) to 5 (every item rated ‘very likely’). Similarly, the 5 items recommended against were averaged to give a Negative Intentions scale from 1 to 5.
Participants were asked “In the last 12 months, has anyone in your family or close circle of friends experienced a similar level of distress to John/Jenny?” and “Did just one of your family or close friends experience this level of distress in the last 12 months, or more than one?”. If the participant knew more than one person, they were told: “Because you know more than one family member or close friend experiencing a similar level of distress, for the next few questions, I want you to think about the one you know BEST”. Participants were asked an open-ended question about what they did to help the person and then a series of questions about specific actions taken that paralleled the questions on intentions. The interviewer recorded ‘yes’ or ‘no’ for each of the 15 items listed above for measuring intentions.
As for the intentions items above, the 10 recommended items were made into a Positive Actions scale by summing the number of ‘yes’ responses to give a score range from 0 (no positive actions carried out) to 10 (all positive actions carried out). Similarly, the 5 items recommended against were summed to give a score range from 0 (no negative actions carried out) to 5 (all negative actions carried out).
Exposure to suicide
Participants were asked “Do you know anyone who has died by suicide?”, with responses recorded as yes or no.
Participants were asked “Have you ever completed any training or course in how to help someone who is suicidal?” The interviewer coded responses as professional training, MHFA, ASIST, QPR or other. The commissioning organization beyondblue is not associated with any of the training programs evaluated in the present study.
Items concerning intentions and actions recommended or not recommended in expert-consensus guidelines were made into scales. Reliability of these scales was quantified with coefficient omega-total using the statistical package R .
The associations between type of training received and quality of intentions and actions were examined using simultaneous linear regression in IBM SPSS Statistics 22. Types of training (professional, MHFA, other) were coded as dichotomous variables and used as predictors of scale scores, with adjustment for type of vignette (dummy coded), sociodemographic characteristics and exposure to suicide. The sociodemographic variables and exposure to suicide were used as covariates because they all had associations (P < 0.05) with having received at least one type of training. Unstandardized regressions coefficients and their 95% CIs are reported for types of training. Effect sizes were measured using Cohen’s d by dividing unstandardized regression coefficients by the sample standard deviation, with values of 0.2, 0.5 and 0.8 being regarded as ‘small’ , ‘medium’ and ‘large’ respectively.
Where associations were found at P < 0.05 for types of training, post-hoc regression analyses were carried out to explore associations with individual intention and action items as the outcome variables. Linear regression was used for associations with the intention items (which were rated on a Likert scale) and binary logistic regression for the action items (which were yes/no). Because these exploratory analyses were post-hoc and involved multiple outcome variables, a conservative Bonferroni approach was used, with alpha divided by the number of items in a scale.