Statistical analysis
hand movements
REGRESSION
Statistical analysis was performed using IBM SPSS version 23. The variables in the categories were: hand movements, time and number of times the structures were visualized before being recognized as such. These variables were assessed using an independent t-test, as these were found to be normally distributed. The data from the experts’ opinion was assessed using a Mann-Whitney U test. Probe movement data from the accelerometer were added up from the three different directions and also divided by time (in seconds), composing the variable ‘total movement’. To assess the relationship between total movements from the accelerometer data and experts’ opinions, a linear regression was performed. For total amount of movements, the logarithm was used in regression analyses because of positive skew. Game data, including differences between the first and the second time level 1 was played, were assessed using a Mann-Whitney U test as data were not normally distributed. The significance of possible confounders was assessed using a Mann-Whitney U test. Fisher’s exact test was used for identifying gender as a possible confounder between groups. Data were reported as a mean and standard deviation (SD), or as a mean rank, where applicable. A 