Table 5.

GLS linear regression: malaria microscopy blood slide staining and reading observation scores

	Unadjusted	Model 2 (adjusted)a
	Percentage point change (95% CI)	Percentage point change (95% CI)
Covariates
RDT observation score	0.5 [0.4, 0.7]***
Malaria blood slide preparation observation score	0.6 [0.5, 0.7]***	0.4 [0.3, 0.5]***
All SOPs for malaria microscopy are present
Yes	Reference
No	− 5.5 [− 12.8, 1.8]
All bench aids for malaria microscopy are present
Yes	Reference
No	− 0.6 [− 7.5, 6.3]
Conducts malaria species identification
Yes	6.5 [1.2, 11.9]*	3.7 [− 1.8, 9.2]
No	Reference	Reference
Uses parasites/µL for parasite quantitation
Yes	7.2 [2.6, 11.8]**	− 0.4 [− 6.1, 5.3]
No	Reference	Reference
Uses “plus system” for parasite quantitation
Yes	− 13.3 [− 17.3, − 9.4]***	− 7.2 [− 12.2, − 2.1]**
No	Reference	Reference
Uses microscopy positive controls
Yes	7.4 [2.4, 12.3]**	3.7 [− 0.9, 8.3]
No	Reference	Reference
Stores stained microscopy slides for cross-checking
Yes	4.5 [0.2, 8.8]*	2.0 [-2.7, 6.6]
No	Reference	Reference
Stock-outs of malaria microscopy consumables
Yes	− 3.2 [− 7.3, 0.9]
No	Reference
Stock-outs of RDTs
Yes	− 3.6 [− 9.5, 2.3]
No	Reference
Periodicity of OTSS assessments
All assessments occurred within a 1 year period	12.3 [4.9, 19.7]**	8.7 [2.7, 14.7]**
All assessments occurred in > 1 year period	Reference	Reference
Number of OTSS visits
1	Reference	Reference
2	1.2 [− 3.7, 6.1]	− 3.1 [− 9.4, 3.2]
3	5.6 [0.7, 10.4]*	− 2.7 [− 8.7, 3.4]
4	11.0 [6.1, 15.8]***	− 0.2 [− 6.5, 6.1]

Statistically significant results are in italics

CI confidence interval, SOP standard operating procedure

Model 2: Wald X² = 96.8 (p < 0.0001); 183 observations

*** p < 0.001; ** p < 0.01; * p < 0.05

^aAn ex-ante pairwise correlation test was run to detect multicollinearity; covariates indicating problematic correlation (≥ 0.55) were not included in the fully adjusted model