Table 1

Characteristics of studies included in final meta-analysis

QuraishiSquireTayalSivitzBergerIversonMarinAdams
Year of publication19972005200620102012201220132016
JournalClinical OtolaryngologyAcademic Emergency MedicineAcademic Emergency MedicineJournal of Emergency MedicineAmerican Journal of Emergency MedicineAmerican Journal of Emergency MedicineAcademic Emergency MedicineJournal of Pediatrics
Country of studyIrelandUSAUSAUSAUSAUSAUSAUSA
Patient populationPaediatric EDEDEDPaediatric EDEDPaediatric EDPaediatric EDPaediatric ED
Number of patients (lesions)23 (23)107 (107)126 (126)50 (50)40 (40)65 (65)755 (873)148 (151)
Number and type of operatorsUnknownUnknown number of emergency physicians and residents5 emergency physicians1 paediatric emergency physician and 1 fellowUnknown number of emergency physicians and residentsUnknown number of paediatric emergency physicians and fellows8 paediatric emergency physicians or fellows8 paediatric emergency physicians, 2 paediatric emergency medicine fellows
Soft tissue ultrasound training or qualificationsUnknown30 min of didactic and hands-on trainingAt least five supervised soft tissue scans30 min didactic, at least 5 soft tissue scans15 min didactic session2 60 min didactic and hands-on training sessions repeated quarterly6-hour training including lecture and hands-on practice1–2 day course, plus at least 25 abscess scans reviewed by ultrasound director
Quality assurance of scansUnknownUnknownUnknownImages recorded and inter-rater agreement measuredNoneInter-rater reliability checked throughout study75% of scans reviewed by blinded sonologist10% of scans repeated by second operator
BlindingNoUnclearTreating clinicians blinded, data collection non-blindedIntermittentYesIntermittentYesTreating clinicians non-blinded; ultrasonographers blinded
US machine and probeUnclearBK Hawk 2102 8 MHz linear; Sonosite Titan 10 MHz linearShimadzu model 400 and 450 7.5 MHz linearSonosite Micromaxx 8–13 MHz linearSonosite Turbo or Micromaxx 10 MHz linearSiemen Sonoline G605 linearSonosite Micromaxx 6–13 MHz or 5–10 10 MHz linear, or 2–5 MHz curved arraySonosite Edge 6–13 MHz linear
US protocolUnclearYesYesYesYesYesYesYes
Reference standardPositive I&DPositive I&D and follow-upUnclearPositive I&DPositive I&DPositive I&DPositive I&D and follow-upI&D or follow-up
Industry sponsoredUnclearNoNoNoNoNoUnclearUnclear
Time to complete US studyUnclearNot recordedNot recordedNot recordedNot recordedNot recordedUnclearNot recorded
Prospective or retrospectiveprospectiveProspectiveProspectiveProspectiveProspectiveProspectiveProspectiveProspective