'The effect of therapeutic rTMS on symptoms of post-traumatic stress disorder' (AsPredicted #202680)
Author(s) Daniel Corp (Deakin University) - daniel.corp@deakin.edu.au Michael Barham (Deakin University) - michael.barham@deakin.edu.au Hannah Bereznicki (Deakin University) - hannah.bereznicki@deakin.edu.au Peter Enticott (Deakin University) - peter.enticott@deakin.edu.au
Pre-registered on 2024/12/03 - 05:50 PM (PT)
1) Have any data been collected for this study already? It's complicated. We have already collected some data but explain in Question 8 why readers may consider this a valid pre-registration nevertheless.
2) What's the main question being asked or hypothesis being tested in this study? 1. What is the effect of therapeutic transcranial magnetic stimulation (TMS) on symptoms of post-traumatic stress disorder (PTSD)?
2. What are the factors that predict inter-individual variability in symptoms of PTSD?
3) Describe the key dependent variable(s) specifying how they will be measured. Clinical rating scales of PTSD symptoms pre and post TMS.
4) How many and which conditions will participants be assigned to? Two conditions: Active TMS and sham TMS.
5) Specify exactly which analyses you will conduct to examine the main question/hypothesis. We will collate de-identified PTSD patient data from previously published/conducted TMS clinical trials in PTSD. Mixed-effects linear regression, using a 'one-step' model as described by Riley et al. (2010), will analyse:
1. Changes in PTSD symptom scores following real TMS.
2. Changes in PTSD symptom scores following sham TMS.
3. Changes in PTSD symptom scores between real and sham TMS.
6) Describe exactly how outliers will be defined and handled, and your precise rule(s) for excluding observations. Data will be winsorized as per Corp et al. (2020, 2021).
7) How many observations will be collected or what will determine sample size? No need to justify decision, but be precise about exactly how the number will be determined. As much data that we can collect from previously published/conducted PTSD clinical trials.
8) Anything else you would like to pre-register? (e.g., secondary analyses, variables collected for exploratory purposes, unusual analyses planned?) We have already analysed data from 5 clinical trials. These preliminary results can be viewed at bignibsdata.com. There will be other co-authors on the eventual publication, who are not listed on this pre-registration, including Belinda Robertson.
