Sanai 2010.
| Study characteristics | |||
| Patient Sampling | "We conducted a case‐control study of patients with HCC and cirrhosis whose clinical records were available for retrospective reviews at Riyadh Military Hospital (RMH) and King Khalid University Hospital (KKUH). Patients with HCC were identified by screening individual hospitals’ computer‐based databases and retrieving the results of all serum AFP performed from January 2006 to March 2008. In total, 210 treatment‐naive patients. A total of 199 unselected, consecutive, control patients with cirrhosis were identified. As a control group, another 197 biopsy‐proven, noncirrhotic chronic hepatitis patients with a serum AFP level available within 6 months of the liver biopsy. Four patients were labelled as HCC, however they did not fulfil the diagnostic criteria described above, and therefore were excluded from the analysis. We did not utilise serum AFP as one of the diagnostic criteria of HCC for the 206 patients included in the analysis in order to exclude incorporation bias." Age range: 13‐93. Males 61% |
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| Patient characteristics and setting | |||
| Index tests | AFP: AFP was measured by a conventional immunoassay (Elecsys 2010, Roche Diagnostics GmbH, Mannheim, Germany). All AFP measurements in HCC cases were recorded prior to any therapy for HCC, cirrhosis or chronic hepatitis. Characteristics of test procedure (sensitivity, specificity, PPV, NPV, likelihood ratios, receiver operating characteristic (ROC) curve, and area under the curve) were used to evaluate the optimal cut‐off value for AFP. | ||
| Target condition and reference standard(s) | HCC: "the diagnosis of HCC was established on the presence of hepatic lesions with typical arterial hypervascularisation and washout in the early or delayed venous phase on liver CT and/or MRI. All imaging studies were read by radiologists with extensive expertise in liver radiology. All patients underwent either CT liver and/or MRI. Needle aspiration or histological sampling was obtained only in conditions when non‐invasive parameters were not diagnostic. We did not utilize serum AFP as one of the diagnostic criteria of HCC for the 206 patients included in the analysis in order to exclude incorporation bias. Control liver cirrhosis group: HCC was excluded by imaging studies [US, CT, and/or MRI], one of which must have been performed at least 6 months following the measurement of AFP." |
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| Flow and timing | The median time between AFP and diagnostic imaging study was 50 days (range 1–364 days). | ||
| Comparative | |||
| Notes | No conflicts of interest reported | ||
| Methodological quality | |||
| Item | Authors' judgement | Risk of bias | Applicability concerns |
| DOMAIN 1: Patient Selection | |||
| Was a consecutive or random sample of patients enrolled? | Yes | ||
| Was a case‐control design avoided? | No | ||
| Did the study avoid inappropriate exclusions? | Yes | ||
| Could the selection of patients have introduced bias? | High risk | ||
| Are there concerns that the included patients and setting do not match the review question? | High | ||
| DOMAIN 2: Index Test (AFP) | |||
| Were the index test results interpreted without knowledge of the results of the reference standard? | No | ||
| If a threshold was used, was it pre‐specified? | No | ||
| Could the conduct or interpretation of the index test have introduced bias? | High risk | ||
| Are there concerns that the index test, its conduct, or interpretation differ from the review question? | Low concern | ||
| DOMAIN 2: Index Test (US+AFP) | |||
| DOMAIN 2: Index Test (US) | |||
| DOMAIN 3: Reference Standard | |||
| Is the reference standards likely to correctly classify the target condition? | Yes | ||
| Were the reference standard results interpreted without knowledge of the results of the index tests? | Yes | ||
| Could the reference standard, its conduct, or its interpretation have introduced bias? | Low risk | ||
| Are there concerns that the target condition as defined by the reference standard does not match the question? | Low concern | ||
| DOMAIN 4: Flow and Timing | |||
| Was there an appropriate interval between index test and reference standard? | No | ||
| Did all patients receive the same reference standard? | No | ||
| Were all patients included in the analysis? | Yes | ||
| Could the patient flow have introduced bias? | High risk | ||