Department of Psychiatry and Psychotherapy, Charité-University Medicine, Campus Benjamin Franklin, Berlin, Germany.
Department of Biopsychology, Ruhr University, Bochum, Germany.
PLoS One. 2014 Jan 8;9(1):e84780. doi: 10.1371/journal.pone.0084780. eCollection 2014.
The Continuous Performance Test-Identical Pairs version (CPT-IP) is a well-established measure of sustained attention, and its more challenging versions are particularly suited to detect subtle processing deficits in patients with schizophrenia. However, while there are few longitudinal samples for the CPT-IP, no study has addressed stability for more than two month in patients with schizophrenia. Assessing long-term test-retest reliability of the CPT-IP would facilitate the ability of clinicians to draw conclusions from studies involving interventions as long term cognitive or pharmacological treatments. The present study assessed 12 month test-retest reliability for the two most challenging versions of CPT-IP (4-digit and shapes) in a matched sample of clinically stable schizophrenia outpatients and healthy controls.
Fifty clinically stable schizophrenia outpatients and 50 healthy controls were assessed with the CPT-IP for the 4-digit and shape conditions. From these, 40 patients and 47 controls were reassessed with an average interval of 12.3 months between test sessions. Test-retest reliability was analyzed with Pearson correlations and results were compared with previous data involving healthy controls and short-term studies in patients with schizophrenia.
Especially d' and hit rate discriminated well between patients with schizophrenia and healthy controls for both CPT-IP conditions and at both test sessions. Healthy controls demonstrated sufficient long term test-retest correlations of d', hit rate and reaction time for both the 4-digit and shape conditions. However, in schizophrenia patients, long-term reliability correlations were at best moderate for d' and hit rate only.
The current study provides further evidence that d' and hit rate yield consistent cross-sectional discrimination sensitivity. At best moderate long-term test-retest reliability of d' in schizophrenia outpatients may be not sufficient for practical use of this measure in long term clinical trials.
连续性能测试-相同对版本（CPT-IP）是一种成熟的注意力持续测试方法，其更具挑战性的版本特别适合检测精神分裂症患者的细微处理缺陷。然而，尽管 CPT-IP 的纵向样本很少，但没有研究在精神分裂症患者中超过两个月的时间来评估其稳定性。评估 CPT-IP 的长期重测信度将有助于临床医生从涉及长期认知或药物治疗干预的研究中得出结论。本研究评估了在临床稳定的精神分裂症门诊患者和健康对照组中，两种最具挑战性的 CPT-IP 版本（4 位数字和形状）的 12 个月重测信度。
50 名临床稳定的精神分裂症门诊患者和 50 名健康对照者接受了 4 位数字和形状条件的 CPT-IP 评估。从这些患者和对照组中，有 40 名患者和 47 名对照组在两次测试之间平均间隔 12.3 个月进行了重新评估。使用 Pearson 相关系数分析重测信度，并将结果与涉及健康对照组和精神分裂症患者短期研究的先前数据进行比较。
特别是 d'和击中率在两种 CPT-IP 条件下和两次测试中都能很好地区分精神分裂症患者和健康对照组。健康对照组在两种 4 位数字和形状条件下均表现出足够的 d'、击中率和反应时间的长期重测相关性。然而，在精神分裂症患者中，d'和击中率的长期可靠性相关性仅为中度。
本研究进一步证明，d'和击中率产生一致的横向区分敏感性。在精神分裂症门诊患者中，d'的最佳中度长期重测信度可能不足以在长期临床试验中实际使用该测量方法。
