Domain

Patient selection

Index test

Reference standard

Flow and timing

Description

Methods of patient selection

How index test was conducted and reported

How reference standard was conducted and reported

Describe patients that did not receive and time interval between index test or reference standard

Signalling questions (yes, no, or unclear)

Consecutive or random sample of patients?

• Yes if the study reported consecutive enrolment or random sampling of patients.

• No if patients were purposefully selected, for example based on previous test results (other tests or reference standard).

• Unclear if the study did not explicitly state consecutive enrolment or random sampling, and it was unclear how patients were sampled.

Index test results interpreted without knowledge of the results of reference standard?

• Yes if it is apparent that ultrasound (and test combinations) results were interpreted without knowledge of reference standard results.

• No if results of ultrasound (and test combinations) were interpreted with knowledge of the reference standard results.

• Unclear if insufficient information on how ultrasound (and test combinations) was interpreted.

Reference standard likely to correctly classify the target condition?

• Yes if the higher quality reference standard was used (that is, culture, microscopic identification of acid fast bacilli, or Xpert).

• No if the lower quality reference standard was used (that is, not coupled with any mentioned in higher quality reference).

• Unclear if insufficient information on the reference standard(s) used.

Was there an appropriate interval between index test and reference standard?

• Yes if abdominal ultrasound and the reference standard(s) (samples taken or clinical diagnosis made) were performed at the same time or if the time interval is less than one week.

• No if the time period between ultrasound and the reference standard is more than one week.

• Unclear if insufficient or no information on the time interval.

Was a case‐control design avoided?

• Yes if a case‐control design was not used.

• No if patients with known disease (cases) and patients without the disease (controls) were clearly enrolled (such that participants are unrepresentative of the spectrum of patients seen in clinical practice).

• Unclear if the study design used was not clearly reported.

Pre‐specified threshold used?

• Yes if the study states the use of one, prespecified, cut‐off value, for example, “abdominal lymph nodes greater than 10mm in the shortest diameter were deemed as a positive result”.

• No if multiple cut‐off values were evaluated and an optimal one (based on maximising test accuracy) was subsequently chosen.

• Unclear if a cut‐off was used but was not reported, or only one cut‐off value was reported, but was not explicitly pre‐specified in the study.

Reference standard results interpreted without knowledge of the results of index test?

• Yes if results of the reference standard are interpreted without knowledge of ultrasound results. However, the clinical reference standard may incorporate ultrasound.

• No if results of the reference standard were interpreted with knowledge of ultrasound results

• Unclear if there is insufficient information on whether or not the reference standard results were interpreted with knowledge of ultrasound results

Did all patients receive a reference standard?

• Yes if all participants received a reference standard.

• No if one or more participants did not receive a reference standard.

• Unclear if there is insufficient information to determine whether or not all patients received a reference standard.

Did the study avoid inappropriate exclusions?

• Yes if no patients were excluded after inclusion in the study.

• No if specific populations were excluded (for example, pregnant patients, elderly), or patients with high CD4 counts were excluded because of low clinical suspicion of TB.

• Unclear if unreported or insufficient information given to make a decision.

Was incorporation bias avoided (inclusion of index test as part of the reference standard)?

• Yes if abdominal ultrasound was not used as part of the reference standard.

• No if abdominal ultrasound formed part of the reference standard.

• Unclear if insufficient information given to make a decision.

Did all patients receive the same reference standard?

• Yes if study participants received the same reference standard (regardless of ultrasound result).

• No if participants did not receive the same reference standard.

• Unclear if there is insufficient information to determine whether or not all patients received the same reference standard.

Were all patients included in the analysis?

• Yes if all participants recruited into the study were included in the analysis.

• No if some participants recruited into the study were excluded in the analysis.

• Unclear if unreported or insufficient information given to make a decision.

Risk of bias¹(high, low, or unclear)

Could the selection of patients have introduced bias?

Could the conduct or interpretation of the index test have introduced bias?

Could the reference standard, its conduct, or its interpretation has introduced bias?

Could the patient flow have introduced bias?

Applicability concerns (high, low, or unclear)

Are there concerns that the included patients do not match the review question?

• High if participants received ultrasound in a tertiary care (referral) centre.

• Low if participants received ultrasound in any setting.

• Unclear if insufficient information to make a decision.

Are there concerns that the index test, its conduct, or interpretation differs from the review question?

• High if, for example, specially trained radiologists performed the ultrasound.

• Low if non‐radiologists performed the ultrasounds.

• Unclear if insufficient information to make a decision.

Are there concerns that the target condition as defined by the reference standard does not match the review question?

• High if studies did not speciate mycobacteria isolated in culture or clinically diagnosed TB cases were not followed up to evaluate treatment response.

• Low if studies did speciate mycobacteria isolated in culture or clinically diagnosed TB cases improved on anti‐TB therapy.

• Unclear if insufficient information to make a decision.

Not applicable