Galluzzi 2010.
| Study characteristics | |||
| Patient sampling | 108 consecutive participants with MCI, referred to an outpatient memory clinic over 24 months Participants were excluded if they had a history or presence of neurological signs of major stroke |
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| Patient characteristics and setting | 90 participants, who had diagnosed by the Petersen 1999 criteria at baseline and had follow‐up assessment, were included in the study; CSF was obtained from 64 participants. Demographic data are reported on 90 participants. Gender: 37 men; 53 women Age: mean 72.05 years; MCI‐MCI: 70.09±7.1; MCI‐AD: 72.2±7.1; MCI‐nAD: 25.5±1.9 APOE ϵ4 carrier: 35; MCI‐MCI: 19; MCI‐AD: 14; MCI‐nAD: 2 MMSE: MCI‐MCI: 26.3±1.9; MCI‐AD: 26.4±1.6; MCI‐other dementia: 73.0±7.1 Setting: secondary care, outpatients ‐ Translational Outpatient Memory Clinic (TOMC), Brescia, Italy |
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| Index tests | CSF: Abeta42 CSF was obtained by lumbar tap between L4 and L5 or L3 and L4 and processed as detailed elsewhere (Frisoni 2009). Levels of Abeta42 protein was determined by commercially available enzyme linked immunosorbent assay (Innogenetics, Belgium). Threshold(s): <500 pg/ml; determined at baseline and based on published criteria (p 2006) At baseline 64 MCI: 29 with 'normal CSF Abeta42 level'; 35 with 'abnormal CSF Abeta42 level' Index test was conducted before clinical follow‐up |
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| Target condition and reference standard(s) |
Target condition: Alzheimer's disease dementia or other forms of dementia Reference standard: NINCDS‐ADRDA criteria Unclear whether clinicians conducting follow‐up a were aware of initial CSF analysis results |
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| Flow and timing |
Duration of follow‐up: 24.0 ± 9.7 months At follow‐up: 39/90 participants converted to dementia (Abstract) Number included in analyses=64: 29 with 'normal CSF Abeta42 amyloid level':15 MCI‐converters (4 MCI‐AD probable; 11 MCI‐non‐AD); 14 MCI‐MCI; 35 with 'abnormal CSF Abeta42 amyloid level': 19 MCI‐converters (16 MCI‐AD probable; 2 MCI‐AD possible; 1 MCI‐non‐AD); 16 MCI‐MCI (from Dr Galluzzi's emails) TP=18; FP=17; FN=4; TN=25 (conversion to AD dementia) TP=19; FP=16; FN=15; TN=14 (conversion to all dementia) TP=1; FP=34; FN=11; TN=18 (conversion to non‐AD dementia) Loss to follow‐up: 44 (16 refused follow‐up assessment; 2 did not follow‐up due to logistic problems; 24 refused LP; 2 failure to reach the arachnoid space due to osteoarthrosis) Withdrawals explained? No 18 participants from the consecutive sample (N=108) were excluded from the study because they did not have a follow‐up assessment. CSF was not available from 26/90 participants: 24 participants refuse the LP procedure; 2 LPs were not performed due to osteoarthrosis |
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| Comparative | |||
| Notes | The trial investigators contacted; they provided data tor the 2x2 table to be completed; emails from Dr Galluzi on 30/3/12 and 5/1/13 | ||
| 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? | Yes | ||
| Did the study avoid inappropriate exclusions? | Yes | ||
| Low | Low | ||
| DOMAIN 2: Index Test All tests | |||
| Were the index test results interpreted without knowledge of the results of the reference standard? | Yes | ||
| If a threshold was used, was it pre‐specified? | Yes | ||
| Low | Low | ||
| 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? | Unclear | ||
| Unclear | Low | ||
| DOMAIN 4: Flow and Timing | |||
| Was there an appropriate interval between index test and reference standard? | Yes | ||
| Did all patients receive the same reference standard? | Yes | ||
| Were all patients included in the analysis? | No | ||
| High | |||