Blood glucose discrimination in insulin-dependent diabetics. Training in feedback and external cues.

Three adults with insulin-dependent diabetes learned to guess their own blood-sugar level. Each day they got feedback on how close the guess was. Some days they also used a short checklist of body cues (thirst, blurry vision, etc.). The researchers switched the two conditions every day to see which worked better.

They tracked how often each person’s guess was within 30 mg/dl of the real reading and how many high-sugar episodes happened each week.

When the checklist was added, guesses hit the 30-point window more often. High-sugar episodes dropped. Feedback alone helped a little, but feedback plus the external cue checklist helped a lot.

All three people showed the same pattern, so the effect was reliable.

Seaver et al. (1976) found the same additive rule in a very different world. Homeowners got fuel-use graphs. When the oil company added a social pat on the back, families saved more oil. The lesson: feedback plus any salient cue beats feedback alone.

Rutter et al. (1987) warned that feedback by itself fades. Young adults with disabilities tracked their work rate. Only the ones taught to ask the boss for comments kept the skill. Again, an external cue rescued feedback.

Cohen (1975) used the same quick-switch design with autistic kids. Exaggerating the key part of the picture (within-stimulus prompt) worked; tacking on extra arrows (extra-stimulus prompt) failed. The diabetes study flips that: here an extra cue wins, probably because the cue is tied to the learner’s own body, not to the task materials.

If you teach self-monitoring, tack on a brief cue sheet. Whether the skill is blood-sugar checks, work speed, or daily living, a one-page list of look-fors keeps the feedback alive. You can build the sheet in five minutes and fade it once the learner’s accuracy stays high.