From 1997 to 2008 there was a significant increase in the percentages of males and females visiting a CAM practitioner. For males, the significant changes were an increase in odds of visiting for those under 50 years, who had a recent complaint, were widower or did hard physical activities. There was a decrease for males who had a university degree, psychiatric complaint or hay fever. For females there was an increase in the odds for those under 50 years, who had a recent complaint or chronic complaint. It was a decrease for those with reported fair global health, psychiatric complaint, hay fever or if they had visited a chiropractor.
The main strength of this study is that it is the largest study to date comparing changes in characteristics of visitors to CAM practitioners. This allowed for both separate analysis for males and females and the analysis of a comprehensive set of explanatory variables. One major limitation was that it was only one question on CAM visits which prevents separate analysis based on frequency of visits. Furthermore, although the question mentioned several types of CAM practitioners, an even more comprehensive list would likely have increased the prevalence since it would enhance the respondents recall. The urban population was underrepresented in this study and a non-responder analysis of the 1997 data  found that older people were more likely not to answer the CAM question than younger people. Nevertheless, the age distribution was similar to other studies [6, 19–21]. Chiropractors are authorised health personnel in Norway and were thus not included in the prevalence figures for CAM visits. This is likely to lower the prevalence compared to countries where chiropractors are CAM practitioners. Furthermore, CAM self care like use of products (herbs, vitamins) or practices (yoga) was not included and the prevalence is thus lower than for studies including such types of CAM. Studies which includes CAM self care , have similar profiles to this study.
The results may be affected by other factors that have not been recorded in both health surveys, i.e. the results may be affected by residual confounding. However, to our understanding, the main variables that lead to a visit to a CAM practitioner were included (general health, specific conditions, chronic conditions, socioeconomic situation). Importantly, the analyses were adjusted for having previously visited a general practitioner and chiropractor which in parts takes account of those who more frequently seek help as well as changes in health care utilisation between both surveys.
There was a substantial increase in the prevalence of CAM visits for both males and females during the 11 years, from 9.4% to 12.6%. This coincides with a general increase in visits to physicians in the same time period, 17% points for males and 11% points for females (calculated from the numbers in table 2). The observed prevalence in this study is close to half of the CAM visits, which included chiropractors, in Australia , where there was an increase from 20.3% in 1993 to 26.5% in 2004. It was similar to a smaller Israeli study where the prevalence of CAM visitors also including chiropractors increased from 6.1% in 1993 via 9.8% in 2000 to 12.4% in 2007 . Since the prevalence of visitors to CAM practitioners excluding chiropractors was similar in Norway and the USA in 2002  and since the prevalence for practitioner based therapies like acupuncture has increased in USA , the prevalence seems to be is similar in the northern hemisphere but considerably lower than in Australia. However, in all countries there has been an increase in practitioner based CAM use during the last decade.
Consistent findings in studies of CAM use have been that middle aged people are the highest users. In this study, the age group among male CAM visitors increasing most was those under 30 years. Also for females the younger age groups had the largest increase. This trend is also observed in the USA were the middle aged do not longer stand out as clearly when 2007  is compared to 2002 , a situation similar to Ireland . This indicates some fundamental changes starting to happen in CAM consumption. The reduced influence of psychiatric complaints in this study could point in the same direction, and in the USA it is also observed that there is a reduction in how frequent psychological problems like anxiety and depression are named as a reason for CAM use [11, 19]. Since having a recent complaint was among the variables with the largest increase from 1997 to 2008 this further strengthens the assumption. It indicates that a larger proportion of the more healthy part of the population is increasing their visits to CAM practitioners. Although this study can give no answers to why this is so, one speculation might be that children who have been taken to a CAM practitioner by their parents have continued to use CAM. This speculation builds on the observed fact that in Norway, there was an increase in the proportion of children among patients visiting homeopaths, from one in ten in 1985 to one in four in 1998 .