It is essential that clear aims and objectives are set for a new intervention when it is being planned. The most important step in any evaluation is matching what you measure or record to the aims and objectives of the intervention.
The Aim of the intervention is the outcome you expect to observe. This outcome may be to raise awareness, to enhance the knowledge or skills of a particular group or to change behaviour. For example the aim of the ‘clunk click every trip was to increase seat belt wearing amongst car occupants in the UK. An intervention may have more than one aim.
The objectives are the way in which you expect to achieve the aim(s); they describe what you expect to change for those you are influencing and/or those who may benefit, by how much and by when. For example, in a seat belt campaign the objectives could be:
- a proportion of the target group will be able to recall the advertisement 3 months after the campaign
- a higher proportion of the target group will report using seat belts immediately after the campaign
- a proportion of the target group will be observed wearing a seat belt six months after the campaign.
Objectives should be 'SMART':
- Specific: clearly identify who will be affected by what is done, and how they will be affected
- Measurable: there are ways of measuring the achievement of the objective
- Agreed: the objective is agreed upon by all those involved in the project
- Realistic: it is realistic, given the available resources
- Time-bound: the objective can be achieved within a defined timeframe
Although the overall goal of all road safety ETP interventions is to prevent road casualties, it is rarely possible to evaluate an ETP intervention by measuring a change in road casualty numbers or rates because it is extremely difficult to link any change in casualties specifically to the intervention. There are several reasons for this:
- ETP interventions are most often short term and one-off, and delivered to relatively small groups of people
- A change in casualties will be influenced by changes in traffic levels and speeds, changes in the number using particular modes of transport, changes to the roads
- There are other social influences on the group who receive the intervention (other education interventions, the media, changes in the lives)
- The very fact that people change as they grow older and gain experience or suffer changes to their health and fitness.
It would take a long term, complex and very expensive evaluation to establish a clear link between an intervention and casualty statistics. Therefore, it is important to set aims and objectives that it is realistic to expect the intervention would be able to meet, such as a change in knowledge, attitudes, skills or behaviour.
See also the Logic Model