However, there is also some evidence that reality in everyday practice is somewhat less 'advanced', for instance because many patients may not wish to be active participants in decision making[10]. The link between patient preferences for participation and actual participation is not very strong [1,6,7,11]. Patient preferences for information do not necessarily translate into information seeking behaviour; nor do patients who express preferences for some form of shared decision making necessarily act on these in the medical encounter [7]. In fact, a consistently very low level of patient question asking is shown in empirical studies throughout the years in a wide range of medical specialties [11-15]. In addition, the preference to participate in medical decision making does not seem to be universal. This preference appears to depend on age (with older people being less interested than younger people[10,16,17]), sex (men less interested than women [16,17]), education (patients with a lower educational level less interested than patients with higher education [16,17]), coping style (patients who are eager for information being more interested than others [18]) and severity of the medical problem (severely ill patients being less interested than healthy ones [19,20]).

Not only are patients said to have changed over the past years. Major changes have also taken place at the doctors' side; e.g. in medical education, organization of health care systems, and quality assurance programs. These changes may have resulted in better quality of care and maybe also in different types of doctors. On the one hand, there seems to be a tendency towards more affect-oriented 'patient-centred medicine' [21-24], which is one of the prevailing paradigms in modern medicine [21]. On the other hand, there has been a major shift towards a more rationalized, biomedically-oriented health care, based on protocols and guidelines (the paradigm of 'evidence based medicine') [25,26]. The scientific base of medicine has expanded tremendously, asking much of doctors in keeping up to date and drawing their attention to the technical side of medicine [27]. To which extent these two paradigms – patient-centred medicine and evidence-based medicine – have influenced the communication process itself cannot be stated with certainty, as empirical evidence about historical shifts in actual physician behaviour in medical encounters is largely absent.

The differences in physician and patient communication behaviour are presented in Table ​Table1.1. The amount of talk by doctors did not significantly differ between the 1986 and the 2002 sample (P = 0.26), but patients did talk less in recent consultations (139 versus 109 utterances, P = 0.02). Compared with the 1986 wave, patients in the 2002 wave asked fewer medical questions, showed less concerns or worries and had fewer process-oriented interventions, like asking for clarification or partnership building. Doctors in 2002 also asked fewer biomedical questions, but they provided significantly more medical information as compared to 1986. Just like the patients, GPs had fewer process-oriented interventions in 2002 and expressed less often their concern about the patients' medical condition.

These findings are in line with the results on patients' side of the communication. All in all, the hypertension patients from the 2002-wave made a substantially smaller contribution to the consultation than their 1986-counterparts, mainly in the process-oriented domain They asked fewer biomedical questions and engaged less in partnership building with the general practitioner, for instance by asking for clarification. Moreover they talked substantially less about what was bothering them. These findings are contrary to expectations, based on the theoretical literature about patient autonomy. In recent publications, it has been argued that patient participation is important for hypertension patients, because, once on medication, the hypertension patient will largely have to manage him/herself [39,41]. Following the literature on patient autonomy, a rise in patient question-asking and process-oriented interventions would have been expected, as modern patients are said to want more information and to be more actively engaged in the medical consultation. For this controversy several explanations are possible. In the first place, it can be argued that patients who visit their general practitioner with hypertension are usually older and therefore don't fit into the model of the modern autonomous patient. Older people are indeed known to have less preference for shared decision making than younger patients[10,16]. This could be either an age-effect or a cohort-effect[10]. However, since no age differences existed between the two samples and a cohort effect would indeed have led to higher patient participation in the 2002 group, age cannot be an explanation for diminished patient participation in our recent sample. Theoretically, it is possible that general practitioners in the 2002 sample were so comprehensive in their information giving that patients had no remaining questions. However, this is quite unlikely. It is at odds with the evidence that doctors consistently underestimate patient's desire for information and that they are not good at eliciting patient preferences[10]. In a recent Dutch study, one third of all general practice patients left the consultation room with unasked questions, 30 % blaming lack of time, 19 % unclear information from the general practitioner and 21 % reported to be too stressed to ask all questions [42]. In a recent qualitative study, only four out of 35 patients said all they wanted to say during the consultation[43]. Maybe today, hypertension patients are monitored more extensively than sixteen years ago and are called in to visit the general practitioner more often for a bodily check-up including blood pressure taking. It is, however, questionable if an increase in the number of visits actually decreases the number of questions asked by patients per visit. Perhaps the most plausible explanation for the low patient participation found in our study is that hypertension patients simply have not turned into active, independent and emancipated consumers, as we are led to believe they would; at least, not during medical consultations. This does not mean that these patients are not autonomous people outside the consultation room. Indeed outside the consulting room patients seem full of ideas on their medical condition and opinions of medical treatment [44].

While this could explain why patient contribution in the medical consultation is low, it does not explain why patients' level of activity is now lower than sixteen years ago. Maybe shifts in physician's behaviour could provide an explanation. Most authors agree that physicians set the agenda for the consultation, and patients follow [7]. Doctors need to create opportunities for patients to feel comfortable in expressing their real worries[45]. 'Being able to talk' has been found to be the most important element in a consultation [10,45], and it is up to doctors to encourage patients to reveal more of what's on their minds[45]. It has been demonstrated that general practitioners' style of listening to the patient will influence what the patient says[46]. Now, the main shift in doctor communication behaviour that we found in this study is a shift from process-oriented towards task-oriented communication – mainly biomedical information giving. Information-giving fits within the first need of what George Engel[38] has called: 'patients double need', i.e.: 'the need to know and understand', a cognitive need related to patients' own task-oriented coping efforts, such as involvement in medical decision making. Information giving clearly does not help to fulfil patients' second need: 'the need to be recognized and understood', an affective need related to patients' emotional coping efforts, such as revealing worries and concerns [45]. Both elements, i.e. supporting patients in shared-decision making for instance by providing as much information as patients need versus facilitating patients to reveal complex agendas, are central in the concept of patient-centeredness [22-24]. Our study shows that Dutch GPs have increased their information giving, but might have lost some of their former capacity to let patients talk along the way. A last possible explanation has to do with the entrance of the computer into the consultation room. None of the GPs from the first cohort were using a computer, while all of the GPs our more recent sample did. And as we have seen, they spent a considerable of amount on computerized record-keeping. Whereas patients used to continue talking when the physician wrote down his findings on paper in the first wave, they tended to remain silent when the physician was using his computer in the second wave. Moreover, it could well be that the computer further contributed to the already more businesslike atmosphere of the recent consultations. Margalit el al[47] found that physician's gazing at the monitor was inversely related to physician engagement in psychosocial questioning and emotional responsiveness as well as to patient socioemotional and psychosocial exchange during the visit and that it diminished the dialogue between physician and patient. It could be that GPs are not yet completely used to computerized record-keeping, and need some time to adjust to this new 'third party' in the consultation room. However, it seems that both research and education should pay more attention to the influence of the computer on the course of medical consultations in order to minimize the disruptive and maximize the beneficial effects of this new companion of doctor and patient.