Table 5 Overview of primary study selection: comparison of trials included as non-RCTs by IQWiG
Systematic review | Search date | Primary study* (Database entry date)†| Personal communication with review authors or other researchers at the publishing institutions | ||||||
|---|---|---|---|---|---|---|---|---|---|
|  |  | Genecov 1998 [18] | McCallon 2000 [22] | Doss 2002 [15] | Scherer 2002 [24] | Kamolz 2004 [21] | Schrank 2004 [25]‡ | Wild 2004 [28]‡ |  |
| Â | Â | (M: 1998-04-02; E; C) | (M: 2001-02-24; C; CIN) | (M: 2002-12-07; E; C) | (M: 2002-07-31; E) | (M: 2004-04-15; E; CIN) | (M: 2004-05-29; E; C) | (M: 2004-05-29; E) | Â |
Reviews considering RCTs and non-RCTs | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Costa/MUHC TAU 2005 [30] | 3/2005 | Non-RCT | Excluded: reason not stated in review (PC: sample size too small) | Non-RCT | Non-RCT | Not reported (PC: excluded) | Not reported (not applicable§) | Not reported (not applicable§) | McCallon 2000. PC (V. Costa): "Did not meet our inclusion criteria (Appendix 1 of the report), i.e., < 9 patients per study arm. This study had 5 patients in each study arm." Kamolz 2004. PC (V. Costa): "Did not meet our inclusion criteria, i.e., did not report clinical outcomes." |
IQWiG 2006 [8] | 5/2005 | Non-RCT | Non-RCT: (allocation was based on alterna-tion) | Non-RCT | Non-RCT | Non-RCT | Non-RCT | Non-RCT | Kamolz 2004. IQWiG: The primary outcome was not a clinical but a surrogate outcome. "The perfusion of both hands was measured using the technique of dynamic laser-fluorescence-videography" [21]. IQWiG included this study because the outcome "pain" was reported in the results section ("All patients tolerated the V.A.C. application without major reports of pain and discomfort" [21]), although the method of pain measurement was unclear. |
Pham/ASERNIP-S 2006 update/[31]|| | 10/2004 (RCTs/non-RCTs) 7/2005 (RCTs) | RCT | RCT | Non-RCT | Non-RCT | Not reported (PC: excluded) | Not reported (PC: excluded) | Not reported (PC: excluded) | Genecov 1998. PC (C. Perera): "Allocation not stated, assumed that a valid method of randomisation had been utilised (critical appraisal in the full accelerated systematic review drew attention to this)." McCallon 2000. PC (C. Perera): "As McCallon et al described this study as an RCT, the authors of the systematic review chose to classify it in the same way, despite the fact that patients were randomised based on alteration." Kamolz 2004. PC (C. Perera): "Regarding the Kamolz study, treatment with VAC was focused upon the period immediately following trauma and thus these were not considered to be chronic, non-healing wounds which were the focus of this review and the manuscript." Schrank 2004; Wild 2004. PC (C. Perera): "Regarding the Wild and Schrank studies, these were not published in English, however you are correct that these studies were published within the search dates. Had these studies been landmark RCTs, they would have been translated and included in the review." |
Reviews considering only RCTs | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Samson/AHRQ 2004 [29] | 6/2004 | Excluded: no outcomes of interest (RCT) | RCT | Not reported (not applicable¶) | Not reported (not applicable¶) | Excluded, as the trial was a non-RCT | Not reported (not applicable¶) | Not reported (not applicable¶) | Genecov 1998. PC (D. Samson): "This study was not a parallel groups or crossover randomized trial, but it was a within-subjects experimental design in which each participant served as his/her own control by receiving Opsite wound dressing and vacuum-assisted closure to separate wounds or wound areas. Since our review was focused on the primary outcome of progress to full wound healing and this study addressed only biopsy findings, this trial was excluded for reporting a non-relevant outcome." McCallon 2000. PC (D. Samson): "Rather than excluding a marginal study like this based on quality concerns, our review selected an inclusive pool of randomized controlled trials, then evaluated study quality, noting that this trial ...used an allocation method that was probably inadequate to be considered true randomization (p. 57)." |
OHTAC 2006 [32] | 3/2006 | Excluded: < 20 patients (RCT) | Excluded: < 20 patients (RCT) | Not reported (not applicable¶) | Not reported (not applicable¶) | Not reported (not applicable¶) | Not reported (not applicable¶) | Not reported (not applicable¶) | Genecov 1998. PC (Medical Advisory Secretariat): "...the Genecov study is a case series of ten subjects and was incorrectly referred to as a randomized controlled trial (RCT). The study was excluded so how it was classified is not of particular relevance." McCallon 2000. PC (Medical Advisory Secretariat): "... excluded based on the information reported in the abstract; there were less than 20 patients and the study was designated as an RCT by MEDLINE. We would not have retrieved the full text to further examine the study to determine how the randomization process was conducted given its exclusion based on number of subjects." |