The Numbers


This section of the website describes how to work out your capacity if you are implementing CAPA. This allows you to know what variety of work you can offer and how much, as well as anticipate the impact of staff changes e.g. someone going on maternity leave.

The methods we describe give you broad estimates of capacity. We make several assumptions, which we will clarify.

In CAPA you guarantee to be able to see all accepted referrals for a Choice appointment. You decide the time frame but we find within 6 weeks of referral suits most service users. However you can choose any time frame that suits your local service or targets that you are required to meet.

CAPA also means you need to be able to offer Core Partnership following Choice without undue delay - we recommend within 4 weeks, certainly no more than 6 (non-urgent). You need clients to have enough time to try out the tasks you agreed in Choice but not so much time that momentum is lost.

To work out how much you can do you need to know:

  1. How many referrals you accept and how much time these take up (your demand for Choice)
  2. How much Core Partnership work results from this demand
  3. How much time you have left to do all other work - Core Partnership, Specific Partnership and non-clinical work - once you have allocated the Choice time.

The Core Clinical Capacity is the clinical appointments available for Choice and Core Partnership. This is made up of the number of appointments, on average, that are offered in each half -day multiplied by the percentage of each full time equivalent staff that are deployed in Choice and Core Partnership.


We have made a number of assumptions. These are that:

  • A clinician can do 2 appointments in a clinical half-day
  • Service users average 7.5 appointments in Core Partnership (note: this is CAMHS data. The range can be wide. See later under ‘Why 3’ for how to adjust the maths if your average is significantly different)
  • Clinicians work 45 weeks per year

Other Guidelines

  • •70% to 66% of Choice appointments end up needing Core Partnership
  • •40% of team time is the maximum that can be allocated to Choice and Core Partnership work if a good range of interventions and other activities are undertaken, including CPD.

There are some fuzzy bits. In practice, not accounting for these in detail does not seem to matter as much as you may think.

What don’t we count?

We do not explicitly take into account co-therapy rates although many audits of how many appointments are used for intervention do account for this. We also don’t account for the number of Core Partnership interventions that progress to Specific ones before the Core average of 7.5 appointments.


No-one really knows what the average number of appointments or clinical hours clients have in Core Partnership work. There is no national collection of this data but we have taken into account these audits:

  • An audit of 7,000 successive new referrals to CAMHS found that the average number of attendances was 4.52 and only 11% of families were still in treatment at six months. 85% of families attended 6 appointments or less and 32% were only seen once. Some of these families were seen by more than one clinician meaning that the number of clinical hours ‘consumed’ was more than the number of attendances. (Hoare et al, 1996). The detail of the co-therapy rate was not recorded, but if we assumed 50% were seen by 2 clinicians then the average number of hours needed per family would be 6.8 and thus 5.8 in Core partnership after Choice.
  • Audit in Richmond found that only 9% of families came for more than 8 appointments those having 8 appointments or less saw one clinician only i.e. needed 8 hours of contact time. (York et al, 2004).
  • Activity data in East Herts (2008) showed that the average number of clinical hours (which includes co-therapy) per family is about 6.5. Also included in this is longer-term Specific work
  • Many other CAMHS across the world have also found their average to be around 7

Caution: it is very easy to feel your treatment average is higher than 7.5 as we notice the families that continue not the ones that stop early. Only adjust if you have good audit data.

Even if it is higher, then this pre-CAPA data. We know that full implementation can reduce the appointment average (in one team in New Zealand it reduced by 30%)

These audits cover all types of CAMHS clinical work - using CAPA terminology they included the equivalent of Choice, Core and Specific Partnership work. The audits show us that the vast majority of families came for 8 appointments or less and needed 8 or less hours of time, even taking into account co-therapy. We have therefore assumed that 7.5 appointments/hours in Core Partnership is a generous assumption. In fact, we suspect it is far less!

We have also ignored DNA’s - those who do not book into Choice (or do but don’t turn up) and those who book Core Partnership but don’t turn up. We exclude these as:

  • Even if they don’t book into Choice you need to ensure you have enough slots in case they do
  • Those who book a Choice but DNA still consume clinical time (even if you spend it doing something else)
  • You need to be able to provide Core Partner- ship slots, even if people then don’t turn up.
  • Audit in Richmond and East Herts have found that there is around 5% DNA for each of these. However, those not coming to the first Core Partnership often come eventually. So we assume 0% DNA in the planning to be generous.