Search strategy and evidence selection

Search strategy and evidence selection

Search strategy

The search strategy was designed to identify evidence on the clinical and cost effectiveness of Secca Therapy in people with faecal incontinence.

The strategy was developed in MEDLINE (Ovid interface), and devised using a combination of subject indexing terms and free text search terms in the title, abstract and keyword heading word fields. The search terms were identified through discussion within the research team, scanning background literature, browsing database thesauri and using the PubMed PubReMiner tool. The strategy reflected the nature of the MIB assessments as rapid evidence reviews, with a relatively pragmatic approach being taken.

The main structure of the draft strategy comprised 2 concepts, combined as: faecal incontinence AND Secca therapy. Terms for the faecal incontinence concept included variants, such as bowel incontinence, anal incontinence and bowel control disorder. Terms for Secca Therapy included terms for the technology used (radiofrequency therapy) and the manufacturer name. The device name was searched as a separate stand-alone term.

The strategy excluded animal studies using a standard algorithm. Non-English language publications were also excluded from the search results. The search was restricted to studies published from 2002 to date; 2002 was identified by the research team as the date when Secca was FDA cleared.

The draft Ovid MEDLINE strategy successfully retrieved all 18 potentially relevant studies identified by the research team at project start. The final Ovid MEDLINE strategy was translated appropriately for the other databases searched. The PubMed search was limited to records not fully indexed for MEDLINE. Reflecting the scope of MIBs, records indexed as conference-related publication types (conference abstract, conference paper, conference proceeding, conference review) were excluded from the Embase search.

The following databases were searched: Cochrane Central Register of Controlled Trials (Cochrane Library, Wiley); Cochrane Database of Systematic Reviews (Cochrane Library, Wiley); Database of Abstracts of Reviews of Effects (Cochrane Library, Wiley); Embase (Ovid SP); Health Technology Assessment Database (Cochrane Library, Wiley); MEDLINE In-Process & Other Non-Indexed Citations and MEDLINE(Ovid SP); NHS Economic Evaluation Database (Cochrane Library, Wiley); PubMed.

Evidence selection

A total of 265 records were retrieved from the literature search. After removal of duplicates, 172 records remained and were sifted against the inclusion criteria at title and abstract level.

Records were sifted independently by 2 researchers. Any disagreements were discussed and agreement was reached in all cases, so a third independent arbiter was not required. The first sift removed 146 records based on the following exclusion criteria:

  • articles of poor relevance against search terms

  • publication types that were out of scope

  • non-English language studies

  • conference abstracts

  • review articles.

Of the remaining 26 studies, full articles were retrieved for 25 (1 was unavailable). Full text assessment was done independently by 2 researchers to identify relevant primary research addressing the key clinical outcomes of interest. Fifteen studies were excluded for the following reasons:

  • review studies/editorials: 13

  • non-English translation unavailable: 1

  • review with primary studies already included: 1.

A total of 10 studies remained, which reported on using the Secca System and addressed the key clinical outcomes of interest.

The retrospective study (Abbas et al. 2012) was excluded from this review due to being of lower quality evidence. Eight of the 9 remaining studies have been reviewed before and summarised in the overview of NICE interventional procedure guidance on endoscopic radiofrequency therapy of the anal sphincter for faecal incontinence. Only 1 study has been published since the guidance (Lam et al. 2014).