Table 1.

Assumptions in estimating service requirements to meet headache-care demand in a population (updated and revised from [29])

Assumption	Argument
The average consultation need per adult patient is 1.25 h per 2 years.	This average is within a wide range of variation. In some countries (eg, Portugal) consultation times are subject to legal recommendations but, otherwise, consultation need varies mostly according to diagnosis and to level within the health-care system. Primary-care needs can usually be met by a first visit of 15–20 min’ duration for diagnosis and impact assessment followed by 10-min visits for monitoring and prescription of acute and preventative therapies, initially after 2–4 weeks then after each 3–6 months (totalling five or six in 2 years). At higher levels of care, first consultations are usually longer (up to 45 min), reflecting case-complexity, but follow-up visits are fewer.
The average consultation need per child or adolescent patient is greater: 2 h per 2 years.	Expert opinion cites the need for additional enquiry into family dynamics, schooling and peer relationships as issues relevant to management success.
No wastage occurs through failures by patients to attend appointments.	This assumption appears manifestly false, but wastage of this sort is difficult to predict in the context of proposals for service improvement. At present, it is commonly discounted by overbooking.
A health-care provider, if working full time on headache without other clinical responsibilities, is available for consultation for 1380 h/year.a	At any level, 1 day per week is assumed for non-clinical work (administration, audit and continuing professional development); each week therefore allows 4 days, each of 7.5 h, of patient-contact time. Only 46 weeks are worked per year.

^aThis assumption allows estimates based on full-time equivalence (see Table 2). It is immaterial that full-time commitment to headache is rare except in level 3