Task Analysis

When teaching a skill like “washing hands”, “doing a puzzle” or “making a sandwich” is difficult, you may want to break the task down into a task analysis. A task analysis looks at every individual step of the task and breaks into a chain. For instance, for washing hands, your task analysis may be broken down into;

1. turn on tap,
2. wet hands,
3. pick up soap,
4. rub soap in hands
5. put soap down
6. rinse hands
7. turn tap off
8. dry hands on towel.

Depending on your client’s abilities, you may want to add or lose some of the detail. This allows you to teach individual steps and assist with acquisition.

The best way to write a task analysis is to ask someone who is an expert in performing that skill, to observe someone performing the task, or to perform the task yourself. This will give you an overview of each step necessary to complete the task successfully. Here is another example in a data sheet. This is for completing a insert puzzle.

The column on the left represents the five steps in this chain. The data is taken as the prompt that is required, FP (Full prompt), PP (Partial Prompt) and IND (independent). The respective data is circled.

Once you have designed your own task analysis for your client and the task you wish to teach, then you will want to begin teaching it to your client.

There are three main ways to begin teaching a skill in this way, backwards chaining, forward chaining or total task analysis. We will discuss these each in turn,

Backwards Chaining

Backwards chaining involves working backwards through the chain. The beginning of the task would be completed for the client, and the client would be required to complete the final step independently. As they begin to acquire the final step, the second from last step is introduced and the client will complete both these steps. The benefit of this is that the client will immediately contact reinforcement when the task is complete.

In the example of the puzzle, on the first four trials I completed the first four steps (red rectangle, yellow square, green oval and blue triangle), by inserting those pieces into the puzzle and then getting my client to do the last piece. I wait for my client to be able to respond independently three days in a row before introducing the next step. On the fifth day, my client is now required to do the blue triangle, and then the yellow circle before I deliver a reinforcer. Here is some fictional data:

At the bottom of the data, I calculate the total number of each prompts used. So on day one there was 1 FP and 0 for PP and IND, on the second day there is 0 for FP and PP, but 1 for IND. I transfer these into percentages (number of prompts given ÷ total number of steps) and graph my data. This is what it would look like:(

 Forward Chaining

Forward chaining involves working forward through the chain in stages. In the beginning the client would only do the first step and then receive a reward. After the require the first step the second step would be introduced. In this example the fictional data looks like this:

On the sixth session the second step is introduced, following three consecutive days of accurate responding on the first step. On the twelve session the third session is introduced, and this continues until all the steps are being performed independently in the sequence. This is how this data looks when transferred into percentages and graphed:

Total Task

Total task involves the client completing every step of the task and the adult providing necessary prompts for each step.

During every trial the client is expected to complete every step, and the level of prompting differs for each step. In the first session, on the first step a full physical prompt is required, but on the fourth step the client is able to do it independently. Here is how I graphed the fictional data for this total task chaining:

Remember to talk to your consultant or BCBA if you are planning to teach a complex skills, they may have some guidance and advice that will help you devise a task analysis and implement it successfully.

Good Luck!

Please keep in mind that the data used here is fictional, and should only be used as a guide to understand the concepts discussed in this blog. Thank you!