Systematic overviews of the literature are increasingly being used to inform policy deliberations as they can pro- vide a comprehensive overview of the evidence landscape in relation to an important area of enquiry. Our overview has done this indicating that there is now substantial evidence that AIT—particularly if administered through the SCIT and SLIT routes—can be effective in improv- ing clinically important outcomes in patients with AR/ ARC with an acceptable safety profile. The evidence base is far less convincing in children due to lack of high qual- ity trials in this age group. Also from systematicreviews the evidence in seasonal disease due to pollen is more consistent than for perennial disease. Importantly, since the cut-point date for evaluation in systematicreviews a number of large, adequately powered studies provide convincing evidence for the efficacy of SLIT for perennial mite allergy.
While the methodological quality of the systematicreviews has been generally increasing over the past dec- ades, there were still up to 27% with low quality scores among those published after 2010. This may of course be a high estimate due to conservative application of the AMSTAR checklist and due to inclusion of a few articles in which the authors described a systematic search but did not aim at writing a systematic review. We have delib- erately applied the AMSTAR checklist twice with more liberal and with more conservative instructions rather than averaging two replicate sets to produce a range of AMSTAR scores for each systematic review. The qual- ity score from a consensus procedure would be likely to lie within this range. Indeed, for the 33 systematicreviews included in both our list and the only previous overview supplying AMSTAR scores , our conserva- tive AMSTAR was consistently lower and our liberal AMSTAR was mostly equal or higher.
There are several methodological challenges in summar- izing evidence from systematicreviews only. There is a substantial number of new trials published in this field every year, and systematicreviews published some years ago may therefore not be based on the most up-to-date evidence. We therefore intended to include Cochrane reviews, because these should be regularly updated. How- ever, this overview clearly shows that this is not the case. We excluded three out of nine eligible Cochrane reviews because they had not been updated after 2007. The deci- sion to exclude Cochrane reviews that had not been updated during the previous five years was arbitrarily cho- sen and is open to debate. However, considering the sub- stantial number of new trials that have been published on this topic in the past few years, we would suggest that including reviews that are more than 5 years old would not reflect the most up-to-date evidence. Although we performed extensive literature searches, the selection of the three non-Cochrane reviews can also be questioned. However, other systematicreviews on the effects of exer- cises for LBP, NP and SP also found more or less similar results. For LBP, Macedo et al.  systematically
Methods/design: We will conduct an overview of SRs based on the Cochrane Handbook for SystematicReviews of Interventions. This overview will be reported following PRISMA 2009 guidelines. Using comprehensive search criteria, we will search the PubMed database to identify relevant SRs published since 2008. Our primary outcomes are gray literature sources and study-level quality in the gray literature. We will include MENA countries with Arabic, English, French, and/or Urdu as primary official languages and/or media of instruction in universities. Two reviewers will independently conduct a multilevel screening on Rayyan software. Extraction of relevant data will be done on Statistical Package for the Social Sciences (SPSS) software. The methodological quality of included SRs will be assessed using the Assessment of Multiple SystematicReviews (AMSTAR) tool. Any disagreements will be resolved by discussion and consensus.
Our overview has several important limitations. Even though our search strategy was thorough, we cannot completely exclude the notion that relevant articles were missed. By evaluating systematicreviews rather than clinical trials, important details of the primary studies may have been lost. Most importantly, the poor quality of the primary data and the systematicreviews is regret- table. Collectively, these limitations limit the conclusive- ness of our findings.
subsequent pregnancies for women who have had previously been diagnosed with GDM (Bottalico 2007; England 2015; Poomalar 2015). Therefore, GDM is a serious public health issue. Successful glycaemic treatments for GDM have the potential to significantly impact on the short- and long-term health for the woman and her baby. Treatments for GDM aim to keep glucose levels within the recommended glycaemic reference range to pre- vent maternal hyper- or hypoglycaemia. Treatments may include dietary and exercise advice, subcutaneous insulin, oral hypogly- caemic agents, such as pharmacological medications, dietary sup- plements or nutraceuticals, antenatal breast milk expression, in- duction of labour or caesarean section (Horvath 2010; Kavitha 2013; Bas-Lando 2014; Forster 2014; Ryu 2014; Kalra 2015). Currently there are several Cochrane systematicreviews that assess different treatment for women with GDM. This makes it difficult for clinicians, consumers, and guideline developers to easily inter- pret the available information. A Cochrane overview of systematicreviews would provide summary evidence of the effectiveness for each treatment for women with GDM and the effects on relevant health outcomes as a one-stop resource for health professionals, consumers and guideline developers to simplify clinical treatment decision-making, and assist with the process of guideline develop- ment.
There are some limitations to conducting overviewreviews of systematicreviews. Firstly, there are con- cerns about double counting individual studies included in different reviews. In this overview we have checked for this and found surprisingly little overlap. Secondly, in reviews of reviews the studies identified are unlikely to have been published in the last few years, given the fact that they have been published in both an original paper and then identified and included in a published review. Thus a review of reviews is less likely to include the very latest research as this would not be captured in existing reviews. This might have particular implications for interventions based on new technologies such as electronic remin- ders for clinicians. We made best efforts to overcome this by running the searches again at the end of 2009 and incorporated 2 additional studies [13,20]. Finally, the reviewers are situated at some distance from the original studies and rely on summaries produced by others of existing primary studies. A further limitation related to the selection of systematicreviews that looked explicitly at interventions designed to get research evidence into practice. A number of systema- tic reviews were excluded as they were not explicit in their inclusion criteria that the studies selected were focused on promoting the use of evidence in practice. Others were excluded as they were not explicit in the main body of the text that the systematic review was focused on promoting the use of evidence in practice.
Tonsillectomy is one of the most commonly performed surgeries in the United States and is typically performed with concurrent adenoidectomy for treatment of obstruc- tive sleep apnea (OSA), especially in the pediatric population. Adenotonsillectomy has become the first-line treatment modality for pediatric OSA. The utility of tonsil- lectomy in pediatric population, especially adult tonsillectomy, has been controversial in the literature. The purpose of this article is to provide an overview of systematicreviews and meta-analyses of tonsillectomy as a surgical option for OSA treatment in various populations, evaluate complication risk, describe confounding variables, discuss successes and limitations, and encourage further research. The specific study search criteria using the PICOS acronym are as follows: 1) “Patients (P)”: pediatric or adult patients with OSA; 2) “Intervention (I)”: tonsillectomy with or without adenoid- ectomy; 3) “Comparison (C)”: outcomes for patients pre- and post-tonsillectomy;
The literature search process yielded 623 records of which 13 met the inclusion criteria of this overview on systematicreviews (Table 1). The search process and reasons of exclusion of the full text articles are provided in the Figure 1 (for reasons of exclusion for each full text article see Additional file 1). Nine of the included reviews targeted individuals with stroke, and four incorporated stroke condition as part of a wider population search (neurologic conditions, adults in community rehabilita- tion, individuals with spasticity or upper extremity im- pairments stroke). All reviews used the International Classification of Functioning, Disability and Health (ICF) as a framework for classifying the outcome mea- sures under different domains. Four reviews incorpor- ate measures at all levels of ICF, one review included measures at impairment level, four at the activity level and 3 on both; and one review searched for measures at the participation level of the ICF alone. Some reviews had a distinct search area including only measures, for example, reflecting the “real-life” function, or used in studies evaluating training with robotic devices [14,21] or accelerometry . One review incorporated the de- velopment of clinical practice guidelines for physiother- apy and one review had the clinical utility as important criteria. More detailed information on description of the included reviews is displayed in Tables 1 and 2.
with the quality of the systematicreviews. Second, this overview could not examine differences in effectiveness that may exist between locally developed and commer- cially available reminder systems due to the limited data. Only three of the included reviews evaluated the effect- iveness of locally developed versus commercially avail- able reminder systems [17,23,27]. The subgroup analysis conducted by Ammenwerth and colleagues demon- strated a higher relative risk reduction for locally devel- oped systems, which they suggested was likely because they are developed to meet local needs, and sites often receive additional resources and support when imple- menting these systems . Garg and colleagues also found that authors who created the decision support system were more likely to report improved performance , but this was not supported by Shojania et al. .
Our overview of systematicreviews with meta- analyses of RCTs provides a comprehensive assessment on the safety of bisphosphonates. This overview indi- cated that bisphosphonates significantly increased the risk of AF, sAF and stroke, but did not significantly increase the risk of atypical fracture or fracture union. It also showed that bisphosphonates could decrease the risk of total adverse CV events, CV death. As the majority of reviews are of poor quality, the relationship between bisphosphonates and some serious adverse events like atypical fracture was often not certain. In despite the vast number of systematicreviews pub- lished, high quality research and more complete inclu- sion criteria are needed.
Our overview has some methodological limitations. First, we limited our literature search to English and German languages because there were no other language skills in our research team and no resources for translating articles. Second, we used modified vote counting; however, we are aware that this type of methodology has strong limitations. Nevertheless, we decided to use modified vote counting because we anticipated that this is the only method to harmonize the results from different types of narrative syn- thesizes. Third, we only analysed therapy-unrelated factors. Consequently, regarding indications where therapy-related factors play an important role (e.g., adverse events in chemotherapy), our evidence is incomplete per se.
Data synthesis in systematicreviews of therapeutic ranges will involve a comparison of outcomes between participants who demonstrate differing serum levels of a drug. Studies vary in how they summarize the serum levels, and this will impact the approach to meta- analysis. For example, studies may compare mean serum levels between those responding to the drug and those not (or experiencing an adverse event or not) (continu- ous data), in which case a meta-analysis of differences in means can be undertaken to provide a pooled estimate of the difference. Alternatively, studies may compare numbers responding and not responding to a drug (or experiencing an adverse event or not) between those with serum levels below and above a particular threshold (dichotomous data). In such studies it would be com- mon to report the relative risk or odds ratio of the event of interest, in which case a meta-analysis of the effect estimates can be undertaken to provide a pooled effect estimate. In any case, it is important to assess for hetero- geneity between studies, and utilising a random effects approach to meta-analysis is recommended where the heterogeneity is found to be large. Potential sources of heterogeneity can also be explored by subgroup analyses and, where possible, meta-regression.
Poor reporting of adverse events (AEs) is a common criticism of CAM research . It is particularly difficult in infants who cannot communicate their responses ef- fectively. AEs in our included reviews were primarily based on parental reports. However, nine of the 16 re- views did report on AEs with the majority reporting that there were none. The acupuncture review  had the highest number of AEs from acupuncture (i.e. bleeding at acupoint, increased hiccoughing), although these are relatively minor. Just six reviews did not report or only partially report on AEs [23, 25, 27, 31, 32, 36]. In addition, several trials ignored safety issues by not pro- viding the reasons why subjects dropped out. Also, due to the small sample sizes of the trials, it is difficult to draw definitive conclusions on safety.
The following databases were searched from 1995 until December 2015: Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations and Ovid MEDLINE(R), EMBASE, CINAHL, PsycINFO, Science Citation Index, Cochrane Library, Database of Abstracts of Reviews of Effects, PROSPERO, Global Health Library, Health Technology Assessment, The Joanna Briggs Institute EBP Database, McMaster Knowledge Translation and WHOLIS. There were no restrictions on language or publication status. The general search terms for MedLine Appendix-2 (Table-1) were reviewed by the authors and a medical librarian and adapted for each database.
Balneotherapy, 1 has been frequently used globally as a complementary and/or alternative therapy. 2 – 5 A recent systematic review (SR) showed that balneotherapy (BT) and spa therapy (ST) could signi ﬁ cantly improve quality of life of patients with knee osteoarthritis. 6 A review that performed a quality assessment of 51 ran- domized controlled trials (RCTs) based on ST identi ﬁ ed each disease based on the International Classi ﬁ cation of Diseases (ICD)-10. 7 The ﬁ ndings identi ﬁ ed 40 stu- dies (78%) that were about “ Diseases of the musculoskeletal system and connective tissue ” (eg, osteoarthritis, low back pain, ﬁ bromyalgia, ankylosing spondylitis, rheumatoid arthritis) and three studies (6%) that were about “ Diseases of the skin and subcutaneous tissue ” (ie, atopic dermatitis and psoriasis).
Criteria for considering systematicreviews for inclusion Our inclusion criteria were: full systematicreviews (with predetermined objectives, eligibility criteria, at least two data bases searched, data extraction, and quality assess- ment of included studies) that included at least one ran- domized trial, which examined the effectiveness of a text messaging intervention (automated or manual, two-way or one-way, irrespective of content) compared to no inter- vention or any other intervention, to improve a health or health-related outcome. The participants could be health workers (professional or lay persons) or consumers of health care (prevention or management). We excluded ab- stracts, non-systematicreviews and other overviews. We also excluded studies that addressed the broader field of mHealth, which would include smart phone applications (of which some may include text messages) and other portable medical devices.
We found clear evidence that AIT administered by the SCIT route is effective in improving medication and symptom scores. The evidence in relation to the effective- ness of SLIT for these outcomes was more mixed. It is interesting to note however, that the review by Compalati et al.  which looked only at HDM AIT shows signifi- cant reductions in both symptom and medication scores for asthma compared to the review by Calamita et al.  which looks at a number of allergens which shows no significant reduction when considering the same out- comes. In terms of lung function no positive result could be concluded for either SCIT or SLIT. With regards to BHR, some of the studies showed an improvement in the SCIT group, but no clear conclusions could be drawn and no improvement in the SLIT group could be dem- onstrated for this outcome. There was considerable vari- ation in results dependent upon which allergen was used and whether multiple or single allergens were adminis- tered with single allergen AIT faring more favorably. The two systematicreviews by Kim et al.  and Chelladurai et al.  which compared the two routes of administra- tion could not conclusively show any difference between the effectiveness of SLIT and SCIT. Furthermore, it was difficult to compare results from these two reviews due to the heterogeneity between them including the fact that one was focused on the pediatric population only whilst the other looked at both adults and children. Fur- thermore, although they both looked at AIT for HDM, they also looked at different allergens with one concen- trating on tree mix and the other pollens. Across all of the reviews, there was considerable variation in results dependent upon which allergen was used and whether multiple or single allergens were administered.
Qualitative and Implementation Methods Group study register, revealed a total of 18 relevant records (6 reviews and 12 protocols) (see Web Appendix A). The titles were registered across 11 Cochrane Review Groups with the Effective Practice and Organisation of Care (5 titles), Consumers and Communication (3) and Public Health (2) Review Groups recording more than one title each. Six of the identified titles included the designation ‘qualitative evidence synthesis’ and two specified that they were ‘mixed methods reviews’. The remainder appeared to use qualitative data to enhance an effectiveness review or did not specify their design.