Clinical and cost-effectiveness of computerised cognitive behavioural therapy for depression in primary care: Design of a randomised trial

<p>Abstract</p> <p>Background</p> <p>Major depression is a common mental health problem in the general population, associated with a substantial impact on quality of life and societal costs. However, many depressed patients in primary care do not receive the care they need. Reason for this is that pharmacotherapy is only effective in severely depressed patients and psychological treatments in primary care are scarce and costly. A more feasible treatment in primary care might be computerised cognitive behavioural therapy. This can be a self-help computer program based on the principles of cognitive behavioural therapy. Although previous studies suggest that computerised cognitive behavioural therapy is effective, more research is necessary. Therefore, the objective of the current study is to evaluate the (cost-) effectiveness of online computerised cognitive behavioural therapy for depression in primary care.</p> <p>Methods/Design</p> <p>In a randomised trial we will compare (a) computerised cognitive behavioural therapy with (b) treatment as usual by a GP, and (c) computerised cognitive behavioural therapy in combination with usual GP care. Three hundred mild to moderately depressed patients (aged 18–65) will be recruited in the general population by means of a large-scale Internet-based screening (<it>N </it>= 200,000). Patients will be randomly allocated to one of the three treatment groups. Primary outcome measure of the clinical evaluation is the severity of depression. Other outcomes include psychological distress, social functioning, and dysfunctional beliefs. The economic evaluation will be performed from a societal perspective, in which all costs will be related to clinical effectiveness and health-related quality of life. All outcome assessments will take place on the Internet at baseline, two, three, six, nine, and twelve months. Costs are measured on a monthly basis. A time horizon of one year will be used without long-term extrapolation of either costs or quality of life.</p> <p>Discussion</p> <p>Although computerised cognitive behavioural therapy is a promising treatment for depression in primary care, more research is needed. The effectiveness of online computerised cognitive behavioural therapy without support remains to be evaluated as well as the effects of computerised cognitive behavioural therapy in combination with usual GP care. Economic evaluation is also needed. Methodological strengths and weaknesses are discussed.</p> <p>Trial registration</p> <p>The study has been registered at the Netherlands Trial Register, part of the Dutch Cochrane Centre (ISRCTN47481236).</p

Geochemical patterns in the soils of Zeeland : natural variability versus anthropogenic impact

Soils can both be a sink and a source for many components influencing our environment. These components may either be beneficial or damaging and for assessing the current environmental condition knowledge about the extent these components are present in the soils is necessary. For the Netherlands the government demanded a nation wide inventory of soil contamination by drafting so called soil pollution risk maps. These maps pertain to levels of priority chemicals relative to their legal thresholds in soil. However, I argue that using methods as used in establishing geochemical baselines and deriving models to estimate the anthropogenic enrichment based on these baselines provide much more insight in the extent of the contamination, or enrichment, of the soils. Therefore a large geochemical survey, using a consequent sampling design and analytical methods, was done in Zeeland, south-west of the Netherlands. The young Holocene marine clayey sediments in the agricultural area were sampled at two depths in the profile, using the deeper layer as a reference. A specific survey was used to estimate the extent of spatial variability. The results indicated a distinct human influence can be discerned and that elements like Cd, Cu, Sn, Sb, Pb, Zn, As are enriched. These elements have also more variability, both in spatial as in attribute space, than the non-anthropogenic influenced elements. The result indicated also that the used legal threshold levels (streefwaarden) are a overestimation of the natural soil background composition. To assess the soil concentrations of DDT and its derivatives and metabolites (sum DDT), the most troublesome organic components due to exceedance of legal limits, likewise statistical methods as for the inorganic assessment were used. The data was taken from local surveys demanded by the authorities using national standards for sampling design and analytical procedures. This research indicated that the sum DDT values were highly variable, in general determined by small scale variability, resulting in limited value of the data