Materials

The questionnaire measure was designed to develop the first principles of a cognitive model of suicidality. The specific aim was to examine whether participants at different stages across the suicidality continuum (Nevers,

Thinkers, Planners, Attempters) hold different patterns of suicide cognitions. Towards this goal, the measuring instrument was formed around six psychometrically tested self-report scales (see Appendix C for further psychometric details on each).

Each variable was measured as follows:

2.3.3.1. Demographic Information

Several relevant demographic variables were collected, including age, gender, educational qualification, relationship status and mental health diagnosis of the clinical participants. Given the association of these variables to suicidality, they were considered relevant to the present study. Age in years was measured as opposed to date of birth so as to limit the amount of identifiable data collected. See Appendix D.

2.3.3.2. Suicide Behaviours Questionnaire-Revised (SBQ-R)

The SBQ-R (Osman et al., 2001) is a 4-item measure asking participants to report their experience of suicidal ideation, planning and attempts. The SBQ-R has been found to be a reliable and valid measure for use with clinical and non- clinical, and adult and adolescent, samples (Gibbs, 2010; Osman et al., 2001). See Appendix E for the scale.

2.3.3.3. Suicide Cognitions Scale (SCS)

The SCS (Rudd, 2007) is an 18-item self-report measure that assesses suicide- specific cognitions. These are characterised by hopelessness, and typically

reflect core beliefs that life is ‘unbearable’ (e.g. “When I get this upset, it is unbearable”), problems are ‘unsolvable’ (e.g. “No one can help solve my problems”), and the individual is ‘unlovable’ (e.g. “I am completely unworthy of love”). Participants rated their level of agreement with each statement using a 4-point Likert scale. Total scores range from 18 to 72, and higher scores indicate greater suicide-specific hopelessness. The SCS has been found to be a reliable and valid measure (Gibbs, 2010; Slee, Spinhoven, Garnefski & Arensman, 2008). See Appendix F for the scale.

2.3.3.4. Brief Resilience Scale (BRS)

The BRS (Smith et al., 2008) is a 6-item, self-report measure of resilience, defined as the ability to bounce back, cope and function well despite adversity or stress (Rutter, 1993). Participants rated their level of agreement with each statement using a 4-point Likert scale. Total scores range from 6 to 24, and higher scores indicate greater resilience. The BRS is a reliable and valid measure (Smith et al., 2008). See Appendix G for the scale.

2.3.3.5. Ten-Item Personality Inventory (TIPI)

The TIPI (Gosling et al., 2003) is a 10-item, self-report measure of the Big-Five Personality Dimensions (Extraversion, Agreeableness, Conscientiousness, Emotional Stability/Neuroticism, and Openness to Experience). Participants rated their level of agreement with each statement using a 4-point Likert scale. It has established reliability and validity (Gosling et al., 2003). See Appendix H for the scale.

2.3.3.6. Patient Health Questionnaire-9 (PHQ-9)

The PHQ-9 (Spitzer, Kroenke, Williams & Patient Health Questionnaire Primary Care Study Group, 1999) is a self-report, 9-item measure of depressive symptoms and their impact on an individual. Total scores range from 0 to 27. Cut-off scores indicating mild (5), moderate (10), moderately severe (15), and severe (20) depression. The PHQ-9 is a reliable and valid measure (Kroenke, Spitzer & Williams, 2001). See Appendix I for the scale.

2.3.3.7. World Health Organization Quality of Life assessment-BREF (WHOQOL-BREF)

Ten items from the self-report WHOQOL-BREF (WHOQOL Group, 1998) were used. Broadly, the items cover life satisfaction across physical and psychological health, social relationships and environment domains. Participants rated their level of agreement with each statement using a 4-point Likert scale. See Appendix J for the scale.

Some measurement scales were adjusted by removing the ‘Neutral’ mid-point option on the Likert scale and standardising scales to a four-point scale, ranging from ‘Strongly Disagree’ (1) to ‘Strongly Agree’ (4). The SCS, BRS and WHOQOL-BREF were originally designed on a 5-point Likert scale, and the Ten-Item Personality Inventory on a 7-point Likert scale. This decision was taken as evidence suggests respondents can be influenced towards selecting a ‘Neutral’ option by ambivalence, lack of motivation, and social desirability (Garland, 1991; Johns, 2005; Krosnick et al., 2002). Respondents may want to avoid the cognitive effort of selecting between conflicting opinions, or even processing the information in the first place, and may want to appear helpful or

avoid giving less socially acceptable answers, particularly in relation to sensitive topics (e.g. Garland, 1991). Krosnick et al. (2002) argued that omitting a ‘Neutral’ mid-point did not negatively impact data quality. For instance, following pre-tests of the scales, it was noted that the results were producing a ‘response set’ located around the mid-point. Omitting the mid-point may avoid this, and may better allow for measurement of meaningful responses. The relative merits of including a mid-point, and how these mid-points are interpreted, have been long-debated in the methodological literature, without any firm conclusions (Garland, 1991)

It is acknowledged that omitting a ‘Neutral’ option on the measurement scales may not allow truly neutral or uncertain responses to be captured, and may have affected the data. Further, removing the mid-point could have put more pressure on participants as it ‘forced’ them to agree or disagree. However, the change was not considered overly detrimental and was ethically approved. It was considered that the value of avoiding the ‘Neutral’ option as a “dumping ground” for uncertain answers (Kulas, Stachowski & Haynes, 2008, p.251) was greater than failing to capture any truly neutral positions. It was also determined that standardising the measures in the full battery of questionnaires as much as possible would enable easier completion, reducing the demands on participants.