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Table 2 Variables (domains) assessed during critical appraisal of primary study validity

From: What are the effects of agricultural management on soil organic carbon in boreo-temperate systems?

Spatial (true) replication2 replicates0
3–4 replicates1
>4 replicates2
Temporal replication≤3 replicates0
4–6 replicates1
>6 replicates2
Treatment allocation (as described for the full experimental design)Purposive (selective)0
Split-/strip-plot/Latin square/blocked/randomised/exhaustive2
Duration of experiment10–19 years0
20–29 years1
≥30 years2
Soil sampling depthShallow (<15 cm) single or multiple sampling0
Plough layer (0–25 cm) single or multiple sampling, or deep (>25 cm) single sampling1
Multiple deep sampling (>25 cm)2
  1. Details of scores assigned to different values are also given