The measures used for data collection were categorized into sociodemographic characteristics, history of testing, and barriers to testing.
Measures employed for data collection (resulting in missing data as regards reasons for emergency ambulance call outs) are acknowledged as a limitation characteristic of studies in this area.
When the interventions being evaluated are aimed primarily at homes, for example, a change in the type of light fittings, 13 an individual's refusal to participate is meaningless, though there may still be a need to obtain individual consent for assessment of outcome measures and for data collection.
The major strength of this study is the use of standard measures and methods for data collection across all populations that would control for many common biases of trials and hospital-based studies.
A set of measures was used for data collection.
The following measures were used for data collection: 1) Tobacco and alcohol use.
Additional potential prognostic factors collected at baseline include, episode duration, pain location, clinical assessment findings (i.e. neurological examination findings), co-morbidity, smoking, height and weight (see Table 1 for details of measures and time points for data collection).
The measures and questionnaires used for data collection have not been validated; however, the information provided by participants increases our understanding of patient views and preferences regarding scale and polish provision.
A limitation of the study, given that low-cost measuring devices were used for data collection and local people were employed as data collectors, is that the collected data are less accurate than those derived from standard environmental research.
Since the end of the 1990s, debate has continued with regard to the most appropriate tool to measure the outcome and for data collection, and different comparison methods have been criticized.
