TABLE 1

Clinical effectiveness of procalcitonin-based protocols to initiate or discontinue antibiotics in patients presenting with acute exacerbations of chronic obstructive pulmonary disease

Participants followed-up (studies)Quality of the evidence (GRADE)Relative effect# (95% CI)Anticipated absolute effects
Risk with standard careRisk difference with procalcitonin-guided protocols
Treatment failure for the index exacerbation834 (5 RCTs)Low¶,+RR 0.81 (0.62–1.06)206 per 100039 fewer failures per 1000 (78 fewer to 12 more)
Length of hospital stay for the index exacerbation1062 (8 RCTs)ModerateMD −0.76 (−1.95–0.43)Mean length of hospital stay was 8.55 daysMD 0.76 fewer days (1.95 fewer to 0.43 more)
Proportion of patients who were prescribed antibiotics on admission984 (7 RCTs)ModerateRR 0.56 (0.43–0.73)791 per 1000348 fewer prescriptions per 1000 (451 fewer to 214 fewer)
Duration of the course of antibiotics776 (6 RCTs)Moderate+MD −3.83 (−4.32–−3.35)Mean duration of course of antibiotics was 8.27 daysMD 3.83 fewer days (4.32 fewer to 3.35 fewer)
Exacerbation recurrence rate at longest follow-up496 (3 RCTs)Low¶,+RR 0.96 (0.69–1.35)205 per 10008 fewer recurrences per 1000 (63 fewer to 72 more)
Re-hospitalisation rate at longest follow-up398 (3 RCTs)Low¶,+RR 1.45 (0.92–2.29)116 per 100052 more admissions per 1000 (9 fewer to 150 more)
Rate of re-hospitalisation due to an exacerbation at longest follow-up298 (2 RCTs)Low,+RR 1.22 (0.71–2.09)135 per 100030 more admissions per 1000 (39 fewer to 147 more)
Overall mortality at longest follow-up1062 (8 RCTs)Moderate+RR 0.99 (0.58–1.69)41 per 10000 fewer deaths per 1000 (18 fewer to 29 more)

Data are presented as n, unless otherwise stated. GRADE (Grading of Recommendations Assessment, Development and Evaluation) working group quality of evidence assessments are as follows. High quality: further research is very unlikely to change the confidence in the estimate of effect; moderate quality: further research is likely to have an important impact on the confidence in the estimate effect and may change the estimate; low quality: further research is very likely to have an important impact on the confidence in the estimate effect and it is likely to change the estimate; very low quality: the estimate effect is very uncertain. RCT: randomised controlled trial; RR: risk ratio; MD: mean difference. #: The risk in the intervention group (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI); : none of the included trials was blinded; +: did not meet optimal information size criterion.