Which data collection method is BEST suited for tracking the frequency of spontaneous requests during PECS implementation?

Frequency recording, specifically momentary time sampling, is the best data collection method for tracking the frequency of spontaneous requests during Picture Exchange Communication System (PECS) implementation. PECS is an augmentative and alternative communication (AAC) system where individuals use pictures to communicate their wants and needs. Spontaneous requests refer to instances where the individual initiates communication by requesting an item or activity without prompting from a communication partner. Frequency recording, in general, involves counting how often a behavior occurs within a defined period. However, simply counting each request (event recording) can be inaccurate when requests happen very frequently, making it difficult to get a precise count. Momentary time sampling addresses this issue. In momentary time sampling, the observer records whether the behavior (a spontaneous request) is occurring at pre-determined, brief intervals (e.g., every 15 seconds, every 30 seconds). The observer does *not* record the behavior if it is happening continuously; they only note if it is present or absent at that specific moment. This method provides an estimate of the behavior's frequency without the observer needing to count every single instance. To calculate the estimated frequency, the number of intervals during which the behavior occurred is multiplied by the reciprocal of the interval length. For example, if the observer recorded a spontaneous request during 5 out of 20 intervals of 30 seconds each, the estimated frequency would be 5 * (60/30) = 10 requests per hour. This method is particularly well-suited for PECS because spontaneous requests can vary greatly in frequency, and momentary time sampling provides a reliable and efficient way to track these fluctuations over time, allowing for informed decisions about PECS implementation and progress monitoring. Other data collection methods, such as event recording or duration recording, are less appropriate. Event recording would be impractical with high-frequency requests, and duration recording (measuring how long a request lasts) is not relevant to tracking the *frequency* of requests.