On Monday, 25th June at 10am (GMT) we had our montly online journal club session and we discussed the paper:
Littlewood, D. L., Kyle, S. D., Carter, L. A., Peters, S., Pratt, D., & Gooding, P. (2018). Short sleep duration and poor sleep quality predict next-day suicidal ideation: an ecological momentary assessment study. Psychological medicine, 1-9.
Here are some notes from thoughts shared in our discussion.
1. Sleep specific concepts
‘Sleep architecture’ refers to the basic structural organization of normal sleep. There are four stages of sleep non-rapid eye-movement (NREM) sleep (which has three stages NREM1, 2,3), and rapid eye-movement (REM) sleep.
‘Sleep onset latency’ refers to the time it takes for someone to fall asleep, from the time that they try to go to sleep. This led to a question as to how accurately do people estimate sleep onset latency? A discrepancy between subjective and objective measures of sleep is quite common in people with insomnia. In such instances people will tend to overestimate sleep onset latency and underestimate total sleep time.
Chronotype – we discussed the notion that some people are more or an early bird versus a night owl. This paper did not examine chronotype, and there are mixed findings across the few studies to look at chronotype in relation to suicidal ideation and behaviour. Generally, evening types are associated with more negative health outcomes. In that sense, it was speculated that we might expect a moderation effect of chronotype on the association between sleep disturbance and suicidal thoughts.
Donna explained that customising sampling schedules to sleep/wake patterns is not common across EMA studies. The group discussed this in relation to adherence, and whether Donna thought the high levels of adherence in this study compared to other EMA work, may be in part due to the customised sampling. Donna agreed with this point, but also added that the watch itself was highlighted as participants as a particularly convenient method of participation.
Donna was asked to share her experience of conducting EMA research, by making recommendations to others who wish to conduct EMA studies in the future. From some evaluation work she has conducted with participants, she highlighted three things. 1) Customise the sampling window to individuals habitual sleep/wake patterns, 2) highlight to people that if they use avoidance or distraction as a method or coping, that is likely to be difficult during participation in this type of study, 3) work with a group of people with lived experience in the development of the procedure.
In the analysis, the six assessments of suicidal ideation per day were used to calculate a mean day-level score of suicidal ideation. Therefore, a case could be made that only one daily assessment of suicidal ideation was necessary rather than six daily assessments. Donna explained that due to the evidence which suggests that suicidal ideation fluctuates across the day that she decided to collect up to 6 assessments as a means to provide a more accurate reflection of day level suicidal ideation.
Moderational analyses focused on entrapment. Why was this variable selected ahead of other psychological variables? Donna explained that this was driven by two factors. First, that this pathway was highlighted by participants in an earlier qualitative study she conducted. Thus testing it in real-time, using quantitative methods was a logical next step. Secondly, from a theoretical perspective, entrapment has been emphasised as a key proximal factor which contributes to the development of suicidal ideation.