Objectives

The Iowa Healthy and Active Minds Study is a four-arm randomised controlled trial of a visual processing speed training programme (Road Tour). This article presents the preplanned interim results immediately after training (6–8 weeks post-randomisation) for the primary outcome.

Design

Within two age strata (50–64 vs ≥65), 681 men and women attending general internal and family medicine clinics were randomised to four training groups: (1) supervised, on-site standard (10 h) dose of Road Tour training; (2) supervised, on-site standard dose of Road Tour training with 4 h of subsequent booster training scheduled to occur at 11 months post-randomisation (ie, no booster training had occurred at the time of this interim analysis); (3) supervised, on-site standard dose of attention control (crossword puzzles) training and (4) self-administered, at-home standard dose of Road Tour training. The primary outcome was the Useful Field of View (UFOV) test. Three intent-to-treat interim analyses were conducted, including (1) multiple linear regression models of composite UFOV scores using Blom rank transformations, (2) general linear mixed effects models and (3) multiple logistic regression models among the 620 participants (91%) with complete data.

Results

In the linear regression analyses of both age strata, random assignment to any Road Tour training group versus the attention control group was significant (p<0.001), with an effect size of −0.558 (adjusted for the Blom rank transformed UFOV score at randomisation). Similar results were obtained for each Road Tour group and within each age stratum and from the general linear and logistic regression models.

Conclusions

Assignment to a standard dose of Road Tour training yielded medium-sized post-training improvements in visual processing speed. Road Tour was equally effective whether administered under laboratory supervision or self-administered in the patient's home and for participants in both age strata (50–64 vs ≥65).

Clinical trial registration number

NCT01165463.

Article summary

Article focus

Normative age-related declines in cognitive functioning leave a pressing need to identify efficient and effective training interventions for older adults.

The Iowa Healthy and Active Minds Study is a four-arm randomised controlled trial of three modes of delivering a computerised visual speed of processing intervention versus an attention control group.

Key messages

The Iowa Healthy and Active Minds Study is the first randomised controlled trial to evaluate the efficacy and effectiveness of Road Tour, a second-generation computerised visual speed of processing intervention.

Statistically significant medium-sized post-training improvements in visual processing speed were observed regardless of delivery method or age strata.

Strengths and limitations of this study

This randomised controlled trial uses a large sample of men and women aged ≥50 years old and overcomes four of the five important limitations (exclusion of 50–64-year-olds, use of a no-contact control group, adherence-conditioned assignment to booster training and reliance on a supervised cognitive training programme) of a previous multisite trial.

The sample was drawn from just one family care centre in which minorities were underrepresented, participants had to have a home computer and internet access, and data on the primary outcome were available only at randomisation and post-training.

Objectives

Gradual age-related cognitive deteriorations are common and are hypothesised to be partially attributable to declines in information-processing speed. The Iowa Healthy and Active Minds Study will evaluate the efficacy and effectiveness of a computerised visual processing speed training programme (Road Tour, Posit Science Corporation, San Francisco, California).

Methods and analysis

Using a 3:3:4:4 ratio within two age strata (50–64 vs ≥65 years old), 681 men and women attending family care clinics were randomised to four treatment groups: 10 h of on-site Road Tour training, 10 h of on-site Road Tour training with 4 h of booster training at 11 months postrandomisation, 10 h of on-site attention control using computerised crossword puzzles (Boatload of Crosswords, Boatload Puzzles, LLC, Yorktown Heights, New York) and 10 h of at-home Road Tour training using the participant's personal computer. The primary outcome, visual processing speed, was assessed at randomisation and post-training (6–8 weeks postrandomisation), and is being reassessed at 1-year postrandomisation using the Useful Field of View test. Five secondary outcomes (Symbol Digit Modalities Test, Trail Making Tests A and B, Controlled Oral Word Association Test, Digit Vigilance Test, and the Stroop Colour and Word Test) were assessed at randomisation and will be reassessed at 1-year postrandomisation. Seven hypotheses will be tested using intent-to-treat analyses involving multiple linear, logistic, Poisson and negative binomial regression.

Ethics and dissemination

Ethics approval was provided by the University of Iowa Institutional Review Board (IRB-03 protocol 200908789). All participants completed signed informed consent prior to enrolment. Road Tour is commercially available from Posit Science Corporation, which provided it to Iowa Healthy and Active Minds Study at no cost. All participants will receive a free copy of Road Tour for unlimited perpetual use at study completion.

Clinical Trial Registration Number

NCT01165463.

Article summary

Article focus

Given that age-related declines in cognitive functioning are part of the normal ageing process, there is a pressing need for efficient and effective training interventions that improve cognitive functioning in older adults.

This protocol paper outlines the design of a study that overcomes several important limitations of a prior, large, multisite randomised controlled trial (RCT) that used memory, reasoning and speed of processing interventions, but found that only the latter effectively translated to improved health outcomes.

This RCT evaluates the efficacy and effectiveness of a second-generation computerised visual speed-of-processing intervention using three modes of delivery (on-site without booster training, on-site with booster training and at-home use) versus an attention control (on-site computerised crossword puzzles without booster training) in improving cognitive processing speed and health outcomes.

Key messages

This is an RCT protocol.

Iowa Healthy and Active Minds Study is the first RCT to evaluate the efficacy and effectiveness of a commercially available computerised visual speed of processing intervention known as Road Tour.

If this intervention is successful, the product vendor pledges to make the computerised intervention software available to governments for widespread distribution and use at a fraction of the current commercial cost.

Strengths and limitations of this study

This study uses six well-established, objective neuropsychological assessments of cognitive processing speed, as well as three highly reliable and valid self-reported measures of health outcomes in a large sample of men and women 50 years old and older.

Although the sample is large, it was drawn from just one large primary care centre in which minorities are under-represented and the key assessments are only conducted at randomisation, after initial training (6-8 weeks postrandomisation) and at 1-year postrandomisation, thereby reducing the opportunity to demonstrate the long-term effects of the intervention.