Table 1 Characteristics of included Discordant Reviews (n = 21)
First Author Year | Objective | Primary outcome | Primary intervention | Country of corresponding author | Health area addressed (ICD-10 Medical Classification) | # Authors per Discordant Review | # Systematic reviews with meta-analysis of RCTs | Discordant Review authors’ conclusion |
|---|---|---|---|---|---|---|---|---|
Bakdach 2020 [13] | Appraise evidence on the management of orthodontically induced white spot lesions (OIWSLs) and choose the best evidence | Incidence of lesions | Topical fluoride toothpaste and/or brush on gel [varnish], or foam | Syria | Caries limited to enamel (K02.0) | 2 | 3 | “Topical fluorides yielded a 25–30% prevention of OIWSLs; however, their effect on reversing OIWSLs is unclear.” |
Chalmers 2015 [26] | Critically evaluate meta-analyses for arthroscopic versus open stabilization techniques for shoulder instability | Recurrent instability | Open versus arthroscopic shoulder stabilization | USA | Other instability of joint (M25.3) | 7 | 2 | “There are no significant differences in failure rates “[i.e. recurrent instability]. |
Bolland 2014 [6] | Explore why discordant results arise across meta-analyses on vitamin D supplements and fracture | Hip fracture | Vitamin D (+/- Calcium) | New Zealand | Fracture of unspecified body region (T14.2) | 2 | 4 | “Each of the 3 meta-analyses concluded that vitamin D alone does not prevent fractures, regardless of dose.” |
Grassi 2018 [31] | Assess and analyze current evidence regarding patellar resurfacing and non-resurfacing in TKA | Risk of reoperation | Patellar resurfacing versus non-resurfacing in total knee arthroplasty | Italy | Unspecified complication of internal orthopaedic prosthetic device, implant and graft (T84.9) | 8 | 5 | “Risk of re-operation was higher after non-resurfacing, however, when the authors considered only high quality RCTs, no differences were reported.” |
Erickson 2015 [32] | Compare nonoperative and operative treatment of patellar dislocations to determine the best available evidence | Recurrent patellar dislocations | Nonoperative versus operative treatment | USA | Recurrent dislocation of patella (M22.0) | 8 | 2 | “Operative treatment of acute patellar dislocations may result in a lower rate of recurrent dislocations than nonoperative treatment.” |
Chen P 2019 [15] | Determine which meta-analysis provides the best available evidence for the use of PRP in the treatment of knee osteoarthritis (KOA) patients | Pain as measured by the WOMAC total score | Platelet-rich plasma (PRP) Injection versus hyaluronic acid (HA) injection or placebo | China | Gonarthrosis, unspecified (M17.9) | 8 | 4 | “Intra-articular PRP injection is more effective in terms of pain relief and function improvement in the treatment of KOA patients than HA and placebo” |
Chen X 2018 [33] | Identify the benefits and disadvantages of unilateral PKP versus bilateral PKP as found in numerous discordant meta-analyses | Pain as measured by the short-term VAS score | Unilateral percutaneous balloon kyphoplasty (PKP) versus bilateral PKP | China | Unspecified osteoporosis with pathological fracture (M80.9) | 10 | 5 | “Unilateral PKP required shorter surgical time and less cement volume, offering better pain relief and quality of life at post-operative short-term follow-ups.”. |
Xu 2017 [34] | Interpret and select amongst discordant MAs and provide surgical recommendations for displaced midshaft clavicle fracture | Fracture non-union | Intramedullary fixation (IF) versus plate fixation (PF) for displaced midshaft clavicle fracture | China | Fracture of clavicle (S42.0) | 7 | 5 | “The best available evidence indicated that the differences between IF and PF were not significant in terms of shoulder function or the rate of treatment failure [includes fracture union]” |
Song 2016 [35] | Assess discordant MAs for treating acute cholecystitis and timing of laparoscopic cholecystectomy | Bile duct injury | Early (within 7 days of the onset of symptoms) versus delayed laparoscopic cholecystectomy for acute cholecystitis | China | Acute cholecystitis (K81.0) | 6 | 6 | “The best available evidence indicated a nonsignificant difference in bile duct injury.” |
Zhao 2015 [18] | Compare surgical and conservative interventions for the treatment of displaced midshaft clavicular fractures | Function as assessed by the constant score | Surgical versus conservative treatment | China | Fracture of clavicle (S42.0) | 3 | 3 | “Surgical treatment provides a lower rate of overall treatment failure and a better functional outcome, but is associated with more implant-related complications.” |
Poolman 2007 [30] | Evaluate reasons for differences in systematic reviews on bone-patellar tendon-bone or hamstring tendon autograft | Knee stability as measured by pivot shift test | Hamstring autograft versus bone-patellar tendon-bone autograft | Canada | Sprain and strain involving (anterior)(posterior) cruciate ligament of knee (S83.5) | 4 | 3 | “The currently available best evidence suggests that hamstring tendon autografts are superior for preventing anterior knee pain, and there is limited evidence that bone-patellar tendon-bone autografts provide better stability.” |
Mascarenhas 2014 [17] | Determine whether double-row (DR) or single-row (SR) rotator cuff repair provides superior clinical outcomes and structural healing | Function as measured by the constant score | Single row (SR) versus double row (DR) rotator cuff repair (RCR) techniques | USA | Rotator cuff syndrome (M75.1) | 7 | 3 | “It was determined that, according to the current best available evidence, DR RCR provides superior patient outcomes and structural healing when compared with SR RCR.” |
Tan 2018 [36] | Compare clinical safety and efficacy of unilateral versus bilateral PKP for treating osteoporotic vertebral compression fracture (OVCF) | Pain as measured by the short-term VAS score | Unilateral versus bilateral percutaneous balloon | China | Unspecified osteoporosis with pathological fracture (M80.9) | 6 | 6 | “Compared with bilateral PKP, unilateral PKP produced a shorter surgery time, smaller dosage of cement, lower risk of cement leakage, and relieved a higher degree of intractable pain at short-term follow-up after surgery.” |
Xing 2016 [37] | Perform a systematic review of overlapping meta-analyses investigating the efficacy and safety of HA for KOA | Early and late knee pain | HA versus placebo | China | Gonarthrosis, unspecified (M17.9) | 7 | 10 | “HA is an effective intervention in treating KOA without increased risk of adverse events.” |
Mascarenhas 2015 [38] | Compare double-bundle (DB) or single-bundle (SB) anterior cruciate ligament reconstruction (ACL-R) | Knee stability measurements by pivot-shift testing | SB versus DB anterior cruciate ligament reconstruction | USA | Sprain and strain involving (anterior)(posterior) cruciate ligament of knee (S83.5) | 7 | 6 | “The current best available evidence suggests that DB ACL-R provides better postoperative knee stability than SB ACL-R, whereas clinical outcomes and risk of graft failure are similar between techniques.” |
Houck 2017 [39] | Compare early versus delayed motion rehabilitation protocols after rotator cuff repair to determine which MAs provide the best available evidence. | Range of motion (general ROM; forward flexion; external rotation) | Early versus delayed motion rehabilitation protocols | USA | Rotator cuff syndrome (M75.1) | 5 | 5 | “The current, best available evidence suggests that early motion improves ROM after rotator cuff repair but increases the risk of rotator cuff retear.” |
Pekala 2019 [40] | Present a comprehensive review based on the most up-to-date MAs on the association of FokI with IDD | Intervertebral disc degeneration (IDD) | FokI (rs2228570) polymorphism | Poland | Intervertebral disc disorder, unspecified (M51.9) | 7 | 7 | “Based on the results from studies published to date, there is no evidence of an association between the FokI polymorphism and IDD in the general population.” |
Zhiyong 2019 [41] | Select the best evidence between unilateral and bilateral balloon kyphoplasty for osteoporotic vertebral compression fractures (OVCFs) | Pain as measured by the short term VAS scores | Unilateral versus bilateral balloon kyphoplasty | China | Unspecified osteoporosis with pathological fracture (M80.9) | 5 | 6 | “Unilateral kyphoplasty is more advantageous, effective and safe, compared to bilateral kyphoplasty for the treatment of OVCFs.” |
Fu 2019 [42] | Provide recommendations for displaced 3-part and 4-part fractures of proximal humerus based on the best evidence | Function as assessed by the constant score | Surgical versus non-surgical treatment | China | Fracture of upper end of humerus (S42.2) | 4 | 4 | “No statistically significant differences were found in the constant score between surgical and non-surgical treatments.” |
Zhao 2015 [43] | Compare intramedullary nail and plate fixation for the treatment of humeral shaft fractures | Non-union | Intramedullary nail versus plate fixation | China | Fracture of shaft of humerus (S42.3) | 4 | 4 | “The differences between intramedullary nail and plate fixation were not significant in fracture union.” |
Guo 2018 [44] | Offer treatment recommendations based on current best evidence of Shenyi Capsule plus chemo versus chemo of non-small cell lung cancer | Disease control rate | Shenyi Capsule plus chemo versus chemo alone | China | Malignant neoplasm of unspecified part of unspecified bronchus or lung (C34.90) | 5 | 4 | “Shenyi capsule plus chemo could increase incidence of short-term efficacy, improve the quality of life and survival rate in comparison to chemotherapy.” |