Rationale for the study
Although the computer is now ubiquitous in the UK primary care consultation, there is as yet no consensus as to how its impact on the consultation should be assessed. The NHS information strategy  has accelerated the process of computerisation, stating that all practices should be computerised by 2005. This strategy aimed to improve the quality of data recorded, drive evidence-based practice and enable easier audit of practice data to explore if national targets are being met. By 1995 it was reported that around 90% of general practitioners (GPs) were using computers during their consultations . The new GP contract , implemented in 2003, has quality targets that can only be met through the use of general practice computers to record markers of the quality of care.
The study team has previously used traditional 'single channel' video recordings of the consultation, to assess the effectiveness of new software in a consultation . However, it proved difficult to carry out this assessment. No gold standard existed for an effective consultation, in the context of this particular software, so a model had to be derived and a rating scale constructed . Assessors had to be trained, and reliability testing performed. The rating scale produced, only achieved borderline reliability. One of the reasons for this was that the assessors found on occasions that it was difficult to determine exactly what was going on in the consultation and how the computer was being used at the time. Often, what was going on and what was being recorded at that precise moment had to be interpreted by the nurse involved whilst replaying the video recording.
A subsequent study was conducted to see if using 'three video channels' overcame the problems associated with using a single video camera . This experiment involved setting up one video camera to record the doctor-patient interaction, the "standard" view as used in the previous study. A second camera focused on the consulting GP's head and shoulders, so that it was easy to discern body language. A third video feed extracted what was entered into the computer. This 'three channel video' set up provided an enormous amount of information, and good insight into how the clinician integrates information. Its drawback was that it was extremely time consuming to analyse. Therefore there is considerable attraction in assessing whether it is possible to use web-cam technology to automate the objective assessment of non-verbal communication between doctor and patient and the degree of attention given to the computer in the consultation.
What is known about the impact of the computer on the consultation?
Herzmark et al  observed that the computer screen requires more attention than paper. Warshawsky  concluded that GPs spent less time interacting with the patient when they used their computer in the consultation. Pringle et al  reported that use of computers can lengthen the duration of the consultation. The computer can be used in different ways during a consultation. Fitter and Cruickshank have identified three patterns of computer use;
1. Minimal users: Clinicians who only record information at the end of the consultation after the patient has left. This has lead to concerns of memory load affecting the completeness of the patient record and the final diagnosis.
2. Conversational users: Clinicians who record information throughout the consultation. Requiring the ability to alternate between tasks.
3. Block users: Clinicians that interrupt the consultation to use the computer, often leaving the patient sitting quietly.
Although there is no hard evidence as to which approach is optimal, styles that mean that the GP does not miss cues from the patient, are thought to be more desirable. Specific training has been developed to convert clinicians from conversational to block styles of computer use, and to identify communication skills that assist in maintaining rapport with the patient whilst using the computer in the consultation . It is possible that this approach will improve the use of the computer in the consultation without prolonging it . Ridsdale and Hudd have highlighted how patients wish to see some, but not necessarily all of the information contained in their computer record , and that generally they think favourably of doctors who use computers during their consultations .
Is there any evidence that patient centred behaviours are beneficial?
Aspects of non-verbal communication such as affirmative head nodding, gaze focused on the patient, leaning forward, affectionate touching and smiling have been found to have an important influence on patients perceptions and satisfaction of the consultation . High levels of patient satisfaction are desirable, as more satisfied patients are associated with higher levels of adherence to treatment, understanding of their condition, adaptive coping, quality of life and health outcome [15, 16]. However, these important elements of the doctor-patient interaction may be compromised if the GP is focused on the computer. Therefore, an effective technique needs to be developed to identify, explore and quantify the balance between making best use of the computer, whist minimising its negative influence on the patient-centred tone of the consultation.
Does use of a camera in the consultation have an adverse influence?
There is no evidence that the use of a video camera interferes significantly with the consultation, it is therefore likely that the same will apply to a physically smaller web-cam. The use of the former during consultations has been widely researched and little impact on practitioner behaviour  or patient satisfaction with consultations , has been found. Video recordings have been used effectively across many academic fields for teaching and training purposes , they are mandatory for the Summative Assessment (a final test of fitness to practice) for doctors wishing to enter General Practice in the UK .
Assessment of the influence of the computer on the consultation
Assessment of the effect of the computer on the consultation can be carried out by exploring when the computer is used and through analysis of verbal and non-verbal behaviour.
It is accepted that there remains a somewhat limited research base about the effective way to use the computer in the consultation . Models have been proposed [5, 22–24] but these are based on consensus and opinion, rather than rigorous scientific method. Much has been described about the use of the computer, but very little has been rigorously evaluated [2, 25].
Assessments of verbal behaviour have been revealed to be reliable and valid. For example, The RIAS (Roter Interaction Analysis System) is typical of the type of coding system that can be used to code verbal behaviour in the GP interaction. Categorising each utterance (either a word or sentence conveying one meaning from the GP and the patient) into 5 categorises; social communication, affective communication, structural communication, health communication and Lifestyle/psychosocial communication. The percentage of verbal communication that focuses on each of these five categories can then be calculated. However, traditional assessments of non-verbal behaviour in consultations use assessments based on video recordings. The recordings lack sufficient detail, are based on subjective assessment and are time consuming to analyse. For example, timing how long the GP leans towards the patient or nods their head . Use of three video channels captures the finer details of the interaction, although the assessment of these recordings remain based on subjective and time consuming analysis . Therefore it is important that assessment methods are developed to increase the objectivity in evaluating the effect of the computer on patient-centred consultations.
Pattern recognition software
Pattern recognition software (PRS) is being increasingly used as a means of interpreting complex movements. One of these uses outside medicine is to interpret video signals such as the monitoring of traffic flows . This technique has also been used in the medical domain for the recognition of gait disorders [29, 30]. However, in general the use of video pattern recognition is at a distance and as yet there are no published reports of its potential use to monitor the influence of the computer on the consultation.
The purpose of this feasibility study was to see if using a standard web-cam and PRS, it would be possible to determine and quantify use of the computer in the consultation. In addition, the investigation sets out to see whether elements of standard assessments of the patient-centred behaviour of the consulting clinician could also be measured using this technique, to overcome some of the problems associated with manually rating consultations. PRS will be an extension of the three channel approach previously described  with the aim to provide quantitative output of non-verbal behaviour.