For students with intensive behavior needs, how many data points are needed to make decisions?

Question: For students with intensive behavior needs, how many data points are needed to make decisions?

Answer: The number of data points to make decisions for behavior change is not a hard and fast science. Unlike progress monitoring for academic decision making, we have to look at a number of factors including the type of behavior that we’re looking at [and] the fidelity in which [the] intervention is being implemented.  But generally I like to look at the recommendations of the single case design researchers, like Rob Horner, who talk about three to five data points as being the number of observations or number of data points necessary to sort of look at things like trend, level, variability of data, and those are the three things that you need to factor in when you’re looking at whether or not you have enough data to make a change. If data is stable, data points are within the context of a very narrow range, then that might be an indicator you have a nice sort of established level of performance. If data is going in the right direction, improving, in the case of problem behavior, then that might also be an indication that your intervention is working. Things like variability, where you have inconsistent performance indicate that maybe two or three data points might not be enough and you need to go on to collect more. So the rule of thumb that I have is to look at a minimum of three data points, look at things like level [and] trend. If you see variability, if you see indicators that the data is not being consistent, maybe collect a couple more data points, and after five data points if you’re not seeing the performance that you’re looking for, that might be a time to re-evaluate and make your adaptation. 

Developed By: 
National Center on Intensive Intervention