Which channels produced patients who reached surgery?

Most bariatric pathways require months of supervised weight management, a psychological evaluation, nutrition appointments and, for insured patients, prior authorisation. That is not a slow sales process — it is clinical and administrative work that has to happen.

The consequence for measurement is the same either way: the advertisement that produced the patient ran two or three quarters before the revenue. Any report comparing this month's spend to this month's cases is comparing unrelated cohorts.

Matching completed cases back to the original enquiry puts the revenue against the period the enquiry came from. It also shows attrition by channel, which is the more interesting finding — channels differ enormously in how many of their enquirers finish the programme.

Free information seminars and webinars are the standard top of funnel in this speciality, and attendance is easy to buy. It is also weakly related to surgery: many attendees are researching for a relative, are not candidates, or will not complete the programme.

When a practice optimises its ad spend toward registrations, it reliably drifts toward the cheapest and least qualified audiences. Ranking channels on completed cases instead is the correction, and it usually reduces the apparent volume while increasing the revenue.

A self-pay sleeve gastrectomy is a single transaction at a known price. An insured case is an authorisation, a contracted rate and a collection cycle, and what the practice is paid bears little relation to what it billed.

Separating them with a payer column keeps the report reconcilable to the practice's accounts. It also stops a handful of cash cases from flattering a channel whose insured volume is collecting at a fraction of charges.

The composition of the enquiry pool has shifted, and any year-on-year comparison drawn without acknowledging that is measuring the wrong thing. A significant share of the people who would once have attended an information session and progressed toward an operation are now pursuing a medical route instead. That does not make the surgical enquiries worse; it makes them different, and it makes a straight comparison of this year's cost per enquiry against two years ago close to meaningless as a judgement on the advertising.

Practices are caught by this in a specific way. Enquiry volume falls, cost per enquiry rises, and the obvious conclusion is that the campaigns have degraded or the agency has stopped trying. What has actually happened is that a segment of the demand left, and the remaining enquiries may convert at a considerably higher rate and to larger cases. Judged on surgery performed rather than on forms submitted, the same campaigns can be performing better than they did before while every intermediate metric says otherwise.

Settling it means ranking the same campaigns on collected surgical revenue across both periods, which is available immediately because the billing records were kept regardless. Practices now running a medical weight management line alongside the surgical one should mark those rows with their own column, so the report shows what each source produced in each line rather than crediting a surgical campaign with medication revenue or, more commonly, ignoring the medication revenue altogether. The same column also protects the surgical ranking, since a source that brings medication patients and few operations should not appear to be carrying the theatre list.

A proportion of patients return for a conversion or a revision several years after their original operation, and some of them were not the practice's patients the first time. Either way the revenue is substantial and it arrives at a distance from any marketing anybody is still measuring. For a practice's own former patients, the original enquiry may be four or five years old and sitting in a system nobody has opened since; for patients operated on elsewhere, the enquiry is new and looks like any other.

Both cases are handled the same way and neither needs anything installed retrospectively. Because the join is on the patient rather than a browser session, a revision performed in 2027 credits the enquiry that produced that patient in 2021, provided both rows are in the files uploaded. That is a genuinely different claim from the one an advertising platform can make, and it is the reason a practice's oldest campaigns can turn out to have a tail that nobody had ever attempted to value.

The practical advice is to upload more history than feels necessary the first time. Five years of enquiries against five years of collected revenue costs nothing extra to analyse, and in a segment where the decision cycle runs to years and the reoperation cycle runs to a decade, the short view is the one that misleads. Marking revision cases with their own column keeps them from inflating the apparent performance of whichever campaign happened to be running when the patient first appeared.