An "on the record" decision refers to Social Security disability and SSI claims pending at the hearing level at the Office of Disability Adjudication and Review (ODAR) that are granted on the record prior to a hearing. An on the record decision can only be a fully favorable decision.
Usually, an on the record (OTR) review is conducted after an on the record request is made. A claim should be clear cut for a good chance at an on the record decision. A strong case would have not just good medical evidence, but also clear evidence of the claimant's functional limitations. If it is clear from the record that the five-step sequential evaluation would yield a finding of "disabled," then an OTR request is a good idea.
One group of claimants that are good candidates for OTR requests are those who are 55 years old or older, are clearly unable to perform their past relevant work, and are limited to unskilled work. Social Security's Medical-Vocational Guidelines direct a finding of "disabled" for such claimants, so an OTR decision is a strong possibility.
Sometimes a case is granted on the record without a formal request. I see this when I have written a hearing memorandum for an approaching hearing. The judge may read the memorandum, review that disability claim file, and then issue an on the record decision without a hearing. Busy ALJs are increasingly recognizing that an OTR decision in an appropriate case saves a great deal of time.