Consider the statistics generated by our PCT in preparation for practice-based commissioning. Its spreadsheet showing costs of procedures and numbers of patients was so detailed that if printed it would probably have reached into the corridor. Yet the information within it is scant because the data is often inaccurate or incomplete. Although the PCT may know the cost of each hospital procedure to the nearest penny, if the numbers of patients being treated are wildly inaccurate, then what's the point? Why waste time?
Statistics are only of value if the data are collected accurately and completely, assessed using the right statistical tools, and presented appropriately. If these three conditions are not met then the result will be garbage. Worse - if we make decisions based on unreliable statistics we may inadvertently be led into planning and doing all the wrong things.
Unfortunately, numbers create a spurious sense of accuracy. Doesn't it sound precise to say that the average height of a particular group of people is 158.17cm? Yet if each person's height was only measured to the nearest half-centimetre such 'accuracy' is quite false.
Our PCT has also given us hospital data about our emergency referrals.
However, this isn't broken down into patients referred by us and those referred by the deputising service. Nor do we know if it includes patients who self-referred to casualty. Each hospital has a vested interest in maximising the numbers of admissions: has anyone checked for double-counting?
Furthermore, are these people really our patients? We frequently receive letters about patients who left our practice long ago, because the hospital hasn't updated their database. What guarantee do we have that the hospital has accurately identified 'our' patients?
As a result this apparently detailed referral data is utterly useless.
Even so, the PCT will almost certainly use it to monitor changes in our referral patterns, though this won't mean anything either. Doubtless they will report any changes to two decimal places - for accuracy, you understand.
- Dr Lancelot is a GP from Lancashire.