The Perceive, Recall, Plan, and Perform System of Task Analysis (PRPP) system is a standardized, two-stage assessment based upon the Australian Occupational Performance Model that uses a task analysis method to examine the effectiveness of executive function relative to information processing that results in the measurement of occupational performance, information processing capacity, as well as other contextual influences (Aubin, Chapparo, Stip, & Rainville. 2012; Chapparo & Ranka, 1997). Clinicians using this system first identify occupational performance errors in stage 1 as a person engages in a task, then determine the cognitive strategy deficits resulting in performance errors during stage 2 (Nott & Chapparo, 2012). Stage 1 uses a behavioral task analysis to determine the steps of the task that need to be assessed through observation and depending on the nature and complexity of the task being performed, the stage 2 cognitive task analysis explores how cognitive strategies are implemented during functional task performance by evaluating the information processing strategies that underpin occupational performance which is divided into 4 areas of cognitive processing identified as central quadrants of performance and include attention and sensory perception (the ability to perceive), memory (ability to recall), response planning and evaluation (ability to plan), and performance monitoring (ability to perform) (Fry & O’Brien, 2002; Nott & Chapparo, 2012). As a client engages in an activity, errors in cognition in each quadrant are identified as those observable behaviors can then be targeted for intervention. The model uses 34 strategies, termed descriptors that are rated on a 3-point scale, indicating how effectively the person applies the 4 outlined cognitive strategies during performance (Fry & O’Brien, 2002; Nott & Chapparo, 2012). The PRPP can be completed in less than 30 minutes.
Research involving 9 occupational therapists found only a moderate level of inter-rater reliability with an intra-class correlation coefficient (ICC) of r = 0.60, which may be a result of model complexities (Nott, Chapparo, & Heard, 2009). Test-retest reliability was better with an ICC of r = 0.88 with a range from 0.83 to 0.88 for each quadrant (Nott et al., 2009). Intra-rater agreement using a Bland-Altman plot was 62.15% (time 1) and 57.63% (time 2) (Nott et al., 2009). In a schizophrenia sample (n = 10) Aubin et al. (2009) showed inter-rater reliability for the PRPP total score to be r = 0.77, for the perceive quadrant it was 0.65, recall 0.65, plan 0.69, and perform 0.63. A study of 28 community-dwelling persons with neurocognitive disorder dementia along with 25 raters found inter-rater reliability to be r = 0.63 for stage 1 and (0.46) for stage 2; however, excellent agreement was found for test reliability for both stages at r = 0.94 and 0.90, respectively (Steultjens, Voigt-Radloff, Leonhart, & Graff, 2012).
The PRPP evaluation is distinct from other assessments in its use of a conceptual model that behaves more like a flow chart that, for the clinician, relies heavily on the visual presentation of the model where unique synergies takes place. The PRPP also measures both task and information processing performance over time as well as the context in which it occurs, affording the clinician a mechanism to measure intervention outcomes at both the level of body structure and function and at the level of activity and participation (Nott & Chapparo, 2012).
Several studies have noted only moderate ICC values for various properties of the assessment where values of 0.70 and higher are usually considered acceptable; however, other studies investigating inter-rater reliability suggest that ICC values of 0.80 or more should be obtained in order to recommend a tool for use in confounding situations or for specific interventions (Donohue, 2006; Slagle, Weinger, Dinh, Brumer, & Williams, 2002) Aubin et al. (2009) argue that these limitations should be taken into account for future studies and in clinical settings.
During the assessment the clinician chooses an activity for the client to perform where their abilities are then rated relative to the four quadrants of the model where close attention is paid to the interplay between them as it is that relationship that determines a person’s level of performance. A total of 34 behavioral descriptors of performance can then be used individually or cumulatively to identify client processing strengths or deficits within each of the four overlapping quadrants representing the PRPP and are featured on the outer rings of the conceptual model (Aubin et al., 2009). The 34 descriptors are typically those observable behaviors, such as maintains and monitors in the perceive quadrant; contextualizes to duration and recalls steps in the recall quadrant; and may be targeted as rehabilitation goals or may contribute to the focus of intervention and refining the decision-making process at the clinical level (Fry & O’Brien, 2002; Aubin et al., 2009).