Kapaki 2001.
| Study characteristics | |||
| Patient Sampling | A total of 99 subjects were included in the study: 38 patients with AD, 14 patients with CJD and 47 controls. Sampling procedure not reported. We only considered data on performance of the index test to discriminate between patients with AD and CJD. Exclusion criteria not reported. |
||
| Patient characteristics and setting | The sample considered in the review comprised of 52 participants: 38 patients with ADD, 14 patients with CJD. Sex: 15 M, 23 F AD; 7 M, 7F CJD Age (y): 68±10 years AD; 59±4 CJD Disease duration (y): 3.6±2.4 AD; 0.4±0.2 CJD Sources of recruitment: Department of Neurology, Athens National University, Greece. Not reported whether inpatients or outpatients |
||
| Index tests | Patients gave CSF samples. The samples were collected in polypropylene tubes, centrifuged, aliquoted, and stored at ‐80°C and analysed. Abeta42 was measured using enzyme‐linked immunosorbent assays, obtained from Innogenetics NV, Gent, Belgium. Threshold: 445pg/ml; not prespecified; Receiver operating characteristics (ROCs) curve analysis was used to define the cut off concentrations of tau protein and Aβ42 with the corresponding optimal sensitivity and specificity (Fig 1B, p402). Were the index test results reported without knowledge of the reference standard? [Not reported] |
||
| Target condition and reference standard(s) |
Target condition: Alzheimer's disease dementia (differential diagnosis of AD dementia from CJD) Reference standard: NINCDS‐ADRDA criteria for AD The clinical diagnosis of CJD was based on progressive dementia of less than 2 years, periodic sharp wave complexes in the EEG recording, and two of the following: (1) myoclonus, (2) visual or cerebeller symptoms, (3) pyramidal or extrapyramidal tract signs, and ( 4) akinetic mutism. All patients had a positive test for 14‐3‐3 protein, a sensitive marker of the disease. The reference standard was performed before applying the index test. Method of confirming diagnosis was not specified for two patients. |
||
| Flow and timing | The interval between established clinical diagnosis and CSF sample collection was not reported. However, it appears that CSF samples were collected short after the diagnosis of dementia was confirmed. Sample included in the analysis: 38 AD; 12 CJD AD vs CJD (50) TP=29; FP=7; FN=9; TN=5 (Fig 1B, p402) Sensitivity=76%; Specificity=42% (Calculated in RevMan5) Missing data: from 2 CJD participants. it was not reported whether those two patients with clinical diagnosis of CJD, which were not confirmed either postmortem or by biopsy, were excluded from the analysis. |
||
| Comparative | |||
| Notes | |||
| Methodological quality | |||
| Item | Authors' judgement | Risk of bias | Applicability concerns |
| DOMAIN 1: Patient Selection | |||
| Was a consecutive or random sample of patients enrolled? | Unclear | ||
| Was a case‐control design avoided? | No | ||
| Did the study avoid inappropriate exclusions? | Unclear | ||
| 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? | Low concern | ||
| 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? | Yes | ||
| Were all patients included in the analysis? | No | ||
| Could the patient flow have introduced bias? | Unclear risk | ||