Evans Rhodri, Joseph-Williams Natalie, Edwards Adrian, Newcombe Robert G, Wright Patricia, Kinnersley Paul, Griffiths Jeff, Jones Mari, Williams Janet, Grol Richard, Elwyn Glyn
Department of Primary Care and Public Health, School of Medicine, Cardiff University, Cardiff, United Kingdom.
J Med Internet Res. 2010 Aug 6;12(3):e27. doi: 10.2196/jmir.1305.
Men considering the prostate specific antigen (PSA) test for prostate cancer, an increasingly common male cancer, are encouraged to make informed decisions, as the test is limited in its accuracy and the natural history of the condition is poorly understood. The Web-based PSA decision aid, Prosdex, was developed as part of the UK Prostate Cancer Risk Management Programme in order to help men make such informed decisions.
The aim of this study was to evaluate the effect of the Web-based PSA decision aid, Prosdex, on informed decision making.
A Web-based randomized controlled trial was conducted in South Wales, United Kingdom. Men aged 50 to 75 who had not previously had a PSA test were randomly allocated to two intervention and two control groups. Participants in the intervention groups either viewed Prosdex or were given a paper version of the text. The main outcome measures were the three components of informed decision making: (1) knowledge of prostate cancer and PSA, (2) attitude toward PSA testing, (3) behavior using a proxy measure, intention to undergo PSA testing. Decisional conflict and anxiety were also measured as was uptake of the PSA test. Outcomes were measured by means of an online questionnaire for the Prosdex group, the paper version group, and one of two control groups. Six months later, PSA test uptake was ascertained from general practitioners' records, and the online questionnaire was repeated. Results are reported in terms of the Mann-Whitney U-statistic divided by the product of the two sample sizes (U/mm), line of no effect 0.50.
Participants were 514 men. Compared with the control group that completed the initial online questionnaire, men in the Prosdex group had increased knowledge about the PSA test and prostate cancer (U/mn 0.70; 95% CI 0.62 - 0.76); less favourable attitudes to PSA testing (U/mn 0.39, 95% CI 0.31 - 0.47); were less likely to undergo PSA testing (U/mn 0.40, 95% CI 0.32 - 0.48); and had less decisional conflict (U/mn 0.32, 95% CI 0.25 - 0.40); while anxiety level did not differ (U/mn 0.50, 95% CI 0.42 - 0.58). For these outcomes there were no significant differences between men in the Prosdex group and the paper version group. However, in the Prosdex group, increased knowledge was associated with a less favourable attitude toward testing (Spearman rank correlation [rho] = -0.49, P < .001) and lower intention to undergo testing (rho = -0.27, P = .02). After six months, PSA test uptake was lower in the Prosdex group than in the paper version and the questionnaire control group (P = .014). Test uptake was also lower in the control group that did not complete a questionnaire than in the control group that did, suggesting a possible Hawthorne effect of the questionnaire in favour of PSA testing.
Exposure to Prosdex was associated with improved knowledge about the PSA test and prostate cancer. Men who had a high level of knowledge had a less favourable attitude toward and were less likely to undergo PSA testing. Prosdex appears to promote informed decision making regarding the PSA test.
ISRCTN48473735; http://www.controlled-trials.com/ISRCTN48473735 (Archived by WebCite at http://www.webcitation.org/5r1TLQ5nK).
对于考虑进行前列腺特异性抗原（PSA）检测以筛查前列腺癌（一种日益常见的男性癌症）的男性，鼓励他们做出明智的决定，因为该检测的准确性有限，而且人们对这种疾病的自然病程了解甚少。基于网络的PSA决策辅助工具Prosdex是作为英国前列腺癌风险管理计划的一部分开发的，旨在帮助男性做出此类明智的决定。
本研究旨在评估基于网络的PSA决策辅助工具Prosdex对明智决策的影响。
在英国南威尔士进行了一项基于网络的随机对照试验。年龄在50至75岁之间且此前未进行过PSA检测的男性被随机分配到两个干预组和两个对照组。干预组的参与者要么查看Prosdex，要么获得该文本的纸质版。主要结局指标是明智决策的三个组成部分：（1）对前列腺癌和PSA的了解；（2）对PSA检测的态度；（3）使用替代指标衡量的行为，即进行PSA检测的意向。还测量了决策冲突和焦虑程度以及PSA检测的接受情况。通过在线问卷对Prosdex组、纸质版组和两个对照组之一进行结局测量。六个月后，从全科医生记录中确定PSA检测的接受情况，并再次进行在线问卷调查。结果以曼-惠特尼U统计量除以两个样本量的乘积（U/mm）报告，无效应线为0.50。
参与者为514名男性。与完成初始在线问卷的对照组相比，Prosdex组的男性对PSA检测和前列腺癌的了解有所增加（U/mn 0.70；95%可信区间0.62 - 0.76）；对PSA检测的态度不太积极（U/mn 0.39，95%可信区间0.31 - 0.47）；进行PSA检测的可能性较小（U/mn 0.40，95%可信区间0.32 - 0.48）；决策冲突较少（U/mn 0.32，95%可信区间0.25 - 0.40）；而焦虑水平没有差异（U/mn 0.50，95%可信区间0.42 - 0.58）。对于这些结局，Prosdex组的男性与纸质版组的男性之间没有显著差异。然而，在Prosdex组中，知识的增加与对检测的不太积极态度相关（斯皮尔曼等级相关系数[rho]= -0.49，P <.001）以及进行检测的意向较低（rho = -0.27，P =.02）。六个月后，Prosdex组的PSA检测接受率低于纸质版组和问卷对照组（P =.014）。未完成问卷的对照组的检测接受率也低于完成问卷的对照组，这表明问卷可能存在有利于PSA检测的霍桑效应。
接触Prosdex与对PSA检测和前列腺癌的了解增加有关。知识水平高的男性对PSA检测的态度不太积极，进行检测的可能性也较小。Prosdex似乎促进了关于PSA检测的明智决策。
ISRCTN48473735；http://www.controlled-trials.com/ISRCTN48473735（由WebCite存档于http://www.webcitation.org/5r1TLQ5nK）
