Table 3 Attributes used to assess study quality
From: A systematic review of phenotypic responses to between-population outbreeding
Design feature | Study attribute | |
|---|---|---|
Internal validity of study | Appropriate comparator lineages used | Were both parental lineages represented for each hybrid cross? 1 point for yes, 0 points otherwise |
Temporal controls | Were outbred and less outbred individuals studied at the same time? 1 point for yes, 0 points otherwise | |
Were all parental lineages observed via controlled crosses? E.g. F1 parental control cross for comparison to F1 treatment cross, F2 for F2 etc.? 1 point for yes, 0 points otherwise | ||
Sampling strategy | Were multiple independent pairs or sets of populations/lineages studied? 1 point for yes, 0 points for only a single pair of lineages | |
External validity of study | Environment for trait observations | Within what environmental context were progeny traits observed? Natural population or native habitat (1 point); environmentally realistic common garden (0.5 points); lab environment (0 points; includes glasshouses, labs, terraria, aquaria) |
Observation window for inbred/outbred individuals | Were phenotypic effects tracked until at least the F2 generation of progeny? 1 point for yes, 0 points otherwise | |
Status of populations/lineages studied | Did the study include natural, naturalized, or cultivated lineages? 1 point where all populations were natural populations, 0 points where naturalized or cultivated lineages were included |