IMPLEMENTATION OF A DTI PROGRAM

Styles of implementation for discrete trial plans differ from one program to another. Generally, a program that provides for errorless learning during the initial stage of a new skill is the first step. The theory behind errorless learning is that students with autism do not learn from their mistakes they only repeat the incorrect ones. Students then move to a less structured program that provides them with feedback, but also allows for mistakes and independent learning. These two programs have many steps that must be implemented consistently between trials as well as between teachers. Students should only change from one teaching format to another following careful analysis of the data collection information that indicates success in the desired skill.

Errorless Teaching

The concept of Errorless teaching is exactly as it sounds. Students are taught skills in a manner that is consistent with not allowing them to make any mistakes. Using the Errorless teaching concept students do not learn an incorrect skill that will have to be corrected or re-taught, but only learn the correct skill. Initially the correct response is the only response that can be given, therefore a student is not able to demonstrate an incorrect answer. (Remember the student does not know what the correct answer is for this procedure)

1. SD – student is given a direction from the teacher
2. R – student begins to perform the response
3. Before the student is able to perform the response the teacher provides a prompt to make sure the student performs the response correctly.
4. The student performs the correct response with adult prompt.
5. The student is positively reinforced for the correct response
6. This trial is repeated several times until it appears he will be able to demonstrate the correct response independently.
7. Following 10 errorless teaching trials a not-prompted trial would occur to assess the student’s correct or incorrect learned response.
8. Prompting should be faded or decreased as soon as indicated by data collection.

   Let’s go back to Paul. In his “office” he is working on labels of items in the classroom. During the initial training Paul would be presented with only one picture of an item and then asked to “give me” the chair (picture). As Paul moves his hand to pick up the picture of the chair the teacher provides a prompt to make sure that Paul gives her the correct picture. Pictures would be taught individually to assure success. As his success at handing the correct pictures of items increases he would be presented with as many as three items to choose from.

   The same format would occur for language acquisition. Now that Paul knows what a chair is, he would be asked to verbally identify the picture. The SD would be “what is this?” As Paul began to speak the teacher would say “chair” so that Paul also said the word immediately following her response. Paul would be reinforced for the correct answer. As Paul becomes more successful with verbally stating what the item is the teacher would decrease her level of prompt from saying the whole word to the beginning sound to no sound at all.

   Paul needs to learn to go to the bathroom independently. He is toilet trained, but requires an adult to help him with all of his clothing needs. The DTI program will focus on teaching Paul to perform the final task before he uses the bathroom (pull down his underwear). Paul is motivated to use the bathroom, so he will try to complete the task. The SD would be “pull down your underwear”. As Paul reaches for his underwear the teachers would help him until his underwear is almost down. Paul can complete the task independently. He then receives reinforcement for completion of the task. As Paul becomes more proficient at the “Underwear down” part of the task the teacher removes her level of assistance. When Paul has that part of the task learned he would move to pulling down his outer pants. (This process is known as an ABA concept of backward chaining, or learning a task from the last part to the first part).

Error Correction

Error Correction is used when the student has learned the correct response but provides an incorrect answer. Error Correction is not used with a student until the student has acquired the requested skill. The Error Correction procedure has two teaching options.

The first procedure does not allow for an additional error on the part of the student. The procedure is applied and the student is only allowed to make the incorrect response one time. Following the first incorrect response the student is immediately prompted with the correct answer.

The second procedure allows the student to recognize an incorrect response and then choose the correct one following the second teacher request. The student is able to choose the incorrect answer one time. Following two incorrect responses the student is re-taught the correct response. The error correction procedure provides data information about how well the student may have learned a skill. Following the second incorrect response the same SD is given and the student is given a full physical prompt for the correct answer. That trial is immediately followed up with the same SD again without the prompt. The last trial is repeated one more time to check for understanding and a correct response.

The school team does not want Paul to make errors during his trials. The data indicates that he has acquired the skill to verbally identify items in the school environment. However, when he makes a mistake he is not able to correct himself but begins to repeat the same incorrect answer over and over. The have chosen the first procedure of error correction for Paul because we do not want him to repeat his incorrect answers more than one time.

Incorrect Response Trial

1. SD – student is given the same direction by the teacher
2. The teacher waits for the response (5 – 8 seconds)
3. R - student response is incorrect
4. The student is not reinforced (negative or positive)
5. The teacher waits for 3 – 5 seconds
6. The same SD is given to the student a second time
7. As the student begins to answer a correct prompt is provided by the teacher
8. The student responds correctly
9. The student is reinforced for the correct response but at a low level
10. The same SD is given by the teacher a third time
11. The teacher waits for the response
12. The student response is correct
13. The student is reinforced for the correct response at a high level

    Once again we are back to Paul. He is having one of those days and some of the previously mastered items are a little difficult for him. The teacher holds up a picture of a chair and gives the SD “ what is it”? He says “desk”. The teacher provides no reinforcement. She puts the card down, waits 5 seconds and holds up the picture again with the SD “What is it”? Before Paul can speak the teacher says “chair”. Paul says, “chair”. The teacher provides reinforcement for the correct answer. She waits 5 seconds again and holds up the same picture of the chair. The same SD is given, “what is it?” This time Paul says “chair”. The teacher provides reinforcement for the correct answer and they move on to the other pictures. The “chair” picture may be presented several times during that program to make sure that Paul does remember that picture item.