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 the ODFS Pace functional electrical stimulation (FES) device for use in patients with drop foot.

The strategy was developed for MEDLINE (Ovid interface). The strategy was 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 use of the PubMed PubReMiner tool. The strategy reflected the nature of the MIB assessments as rapid evidence reviews, with a relatively pragmatic, focused search approach being used.

The main structure of the search strategy comprised two concepts:

1) dropped foot

2) ODFS Pace FES device.

The search concepts were combined as follows: dropped foot AND ODFS Pace FES device.

Terms for the ODFS Pace FES device concept were based on the key action of the device – functional electrical stimulation of the common peroneal nerve. The strategy also included 3 stand‑alone search lines on the manufacturer and device names (lines 18–20).

The strategy excluded animal studies using a standard algorithm. Non‑English language publications were also excluded from the search results. No date limit was applied to the strategy.

The MEDLINE strategy was translated appropriately for the other databases searched. The PubMed search was limited to records that were not fully indexed on MEDLINE. Conference‑related records 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 and MEDLINE in Process (Ovid SP)

  • NHS Economic Evaluation Database (Cochrane Library, Wiley)

  • PubMed.

Evidence selection

A total of 972 records were retrieved from the literature search. After de‑duplication, 590 records remained. The title and abstracts of all 590 records were screened independently by 2 reviewers, against the following inclusion and exclusion criteria:

Inclusion criteria:

  • use of the Odstock functional electrical stimulator

  • patients with drop foot

  • comparators are physiotherapy or mechanical devices

  • useful outcomes listed.

Exclusion criteria:

  • low number of patients (that is, <10)

  • non‑English language studies

  • conference abstracts

  • review protocols

  • non‑comparative studies.

Disagreements between the 2 reviewers were resolved through discussion, and, where necessary, through consultation with a third reviewer. This first sift excluded 548 papers. A further 10 papers were not retrieved because they were deemed not to be relevant, high quality studies based on the abstracts. Full records were retrieved for the remaining 32 papers. A list of the papers that were not retrieved is provided below:

  • Bosch PR, Harris JE, Wing K et al. (2014) Review of therapeutic electrical stimulation for dorsiflexion assist and orthotic substitution from the American Congress of Rehabilitation Medicine stroke movement interventions subcommittee. 95: 390–6

  • Dunning K, O'Dell MW, Kluding P et al. (2015) Peroneal stimulation for foot drop after stroke: A systematic review. American Journal of Physical Medicine and Rehabilitation 94: 649–64

  • Granat MH, Maxwell DJ, Ferguson AC et al. (1996) Peroneal stimulator; evaluation for the correction of spastic drop foot in hemiplegia. Archives of Physical Medicine and Rehabilitation 77: 19–24

  • Hayes Inc. (2011) Functional Electrical Stimulation (FES) for treatment of foot drop in multiple sclerosis patients. Healthcare Technology Brief Publication

  • Lairamore CI, Garrison MK, Bourgeon L et al. (2014) Effects of functional electrical stimulation on gait recovery post‑neurological injury during inpatient rehabilitation. Perceptual and Motor Skills 119: 591–608

  • Roche A, o Laighin G, Coote S (2009) Surface‑applied functional electrical stimulation for orthotic and therapeutic treatment of drop‑foot after stroke: a systematic review. Physical Therapy Reviews 14: 63–80

  • Sabut SK, Bhattacharya SD, Manjunatha M (2013) Functional electrical stimulation on improving foot drop gait in poststroke rehabilitation: A review of its technology and clinical efficacy. Critical Reviews in Biomedical Engineering 41: 149–60

  • Sabut SK, Sikdar C, Kumar R et al. (2011) Functional electrical stimulation of dorsiflexor muscle: Effects on dorsiflexor strength, plantarflexor spasticity, and motor recovery in stroke patients. NeuroRehabilitation 29: 393–400

  • van der Linden ML, Hazlewood ME, Hillman SJ et al. (2008) Functional electrical stimulation to the dorsiflexors and quadriceps in children with cerebral palsy. Pediatric Physical Therapy 20: 23–9

  • Wilder RP, Wind TC, Jones EV (2002) Functional electrical stimulation for a dropped foot. Journal of Long‑Term Effects of Medical Implants 12: 149–59

The second sift was done against the same inclusion and exclusion criteria. Again, disagreements between the 2 reviewers were resolved through discussion and consultation with the third reviewer. A total of 21 papers were excluded for the following reasons:

  • intervention not relevant (n=19)

  • record was a presentation (n=1)

  • record was a duplicate (n=1).

Of the remaining 11 studies, 6 representing the best quality evidence, which included all relevant outcomes to the treatment, were selected.

All papers were assessed for methodological quality using the checklists provided within the NICE guidelines manual: appendices B-I.