Search strategy and evidence selection

Search strategy and evidence selection

Search strategy

1. Databases were searched from inception to January 2015 including MEDLINE(R) In‑Process & Other Non‑Indexed Citations and MEDLINE(R) (via Ovid); Embase (via OVID); Cochrane Library; CAB Abstracts; Web of Science Science Citation Index. The keywords peptest, lateral flow test, saliva, sputum, pepsin, GERD, GORD, and reflux were used for the searches.

2. The internet was searched using the above keywords.

3., WHO ICTRP, and Current Controlled Trials were also searched for ongoing trials.

4. Information provided by the manufacturer was thoroughly checked for relevant studies. Information provided by the manufacturer in supporting this briefing was checked to identify any further information.

5. The manufacturer's website was thoroughly investigated.

Evidence selection

The references and citations from the above searches were sifted through to find any relevant material, using the inclusion criteria as follows:


Adults or children with suspected GORD. Potentially, the test could be used in secondary care settings (to confirm whether symptoms or diagnoses may be related to GORD) or in primary care (to confirm symptomatic diagnosis of GORD).


Peptest diagnostic test.


When considering diagnostic test characteristics Peptest could be compared with:

  • other point of care tests (if available)

  • clinical diagnosis

  • endoscopic diagnosis (this could be considered the reference standard for GORD diagnosis; however, NICE guidance lays out referral criteria, as a clinical diagnosis is often appropriate and confirmation of diagnosis by endoscopy is not always needed)

  • other tests used in standard clinical practice to diagnose reflux

  • diagnosis by treatment effectiveness of antacids and others.

Care pathways where Peptest could be introduced as an additional or optional test include:

  • initial presentation of dyspeptic symptoms

  • failure of initial antacid treatment

  • before prescription of proton pump inhibitors

  • to know whether to refer to endoscopy

  • instead of referral to endoscopy (unlikely as endoscopy will also identify more serious pathologies including cancer and Barrett's oesophagus)

  • to determine following initial investigations whether GORD is the cause of symptoms or conditions

  • to determine whether GORD is the cause of non‑dyspeptic symptoms or conditions.


Sensitivity, specificity, positive predictive values, negative predictive values, diagnostic yield and therapeutic yield.