'Childhood Trauma and Video Games Among Perpetrators of Mass Shootings'
Created: 02/15/2021 09:26 AM (PT)
This is an anonymized version of the pre-registration. It was created by the author(s) to use during peer-review.
A non-anonymized version (containing author names) should be made available by the authors when the work it supports is made public.
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?
H1: Mass shooters have experienced more childhood trauma (or abuse) compared to individuals that have not become mass shooters.
H2: Mass shooters have experienced more childhood bullying compared to individuals that have not become mass shooters.
H3: Mass shooters have experienced played more violent video games compared to individuals that have not become mass shooters.3) Describe the key dependent variable(s) specifying how they will be measured.
The dependent variable is mass homicide perpetration and whether they are different from each other throughout the three predictor variables.4) How many and which conditions will participants be assigned to?
This is not an experiment. All data is archival. I will not be recruiting participants for this study. Therefore, no participants will be assigned to conditions. The predictor variables are childhood trauma (or abuse), childhood bullying and violent video games.5) Specify exactly which analyses you will conduct to examine the main question/hypothesis.
One Sample T-test will be used to analyze the archival data of which mass homicide perpetrators from the Mass Shooters Database, experienced which predictor variables. The one sample t-test will specifically compare the mass homicide perpetrators against the proportions from the other samples within the predictor variables that will be focused on. Therefore, one sample t-test will compare the mass homicide perpetrators against the analyzed proportions of childhood trauma or abuse (González et al., 2016). A second, one sample t-test would be performed to compare he mass homicide perpetrators against the analyzed proportions of childhood bullying (Wong et al., 2013). A third, one sample t-test would be performed to compare he mass homicide perpetrators against the analyzed proportions of violent video games (Olson et al., 2007).6) Describe exactly how outliers will be defined and handled, and your precise rule(s) for excluding observations.
The only outliers or exclusions that would need to be handled will only be if there is significant missing data on a participant within the archival data.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.
The archival data that will be used has gathered data on 172 mass homicide perpetrators.8) Anything else you would like to pre-register?
(e.g., secondary analyses, variables collected for exploratory purposes, unusual analyses planned?)
We are using pre-existing databases, but have not looked at the data compiled together. The archival data from the Mass Shooter Database will be compiled with the archival data found on each of the three predictor variables to determine if there is a correlation. The purpose is to determine if a correlation exists between mass homicide perpetrators and their experiences as a child such as experiencing the three predictor variables.