The present study used the DISCERN instrument to assess the quality of consumer health information provided by 33 web sites of vendors selling cannabis to consumers in Canada. Although online vendors facilitate easier access and convenience to individuals wishing to purchase cannabis, the quality of health information on these web sites was generally found to be low. Many of these web sites failed to discuss uncertainties surrounding the research evidence about cannabis, the impact of cannabis use on quality of life, alternatives to cannabis use, risks associated with cannabis use, and lacked references to support claims on effects and benefits of use. These findings should warrant concern among HCPs and researchers, considering that patients may use these vendors' web sites as primary sources of information informing their decision to purchase/consume cannabis. Physicians and other healthcare providers (HCPs) should be aware of these findings and appropriately caution patients who express interest in cannabis use.
A number of reasons may explain why the quality of consumer health information found on most web sites we assessed was low. First and foremost, these web sites were commercial in nature; vendors are motivated to present information in a sensational rather than objective manner, aiming to persuade consumers to buy their products. Naturally, this results inthe provision of biased and unbalanced information, with a greater focus on the benefits of cannabis use and less focus on the risks, as evident by the present study's results, along with other published studies [26, 27]. Presenting information that could potentially detract consumers from buying products, such as the side effects of cannabis use, is not in the interest of many online vendors [28]. Additionally, as evident by the aims and goals provided by many of these web sites, they are primarily concerned with selling their products as opposed to educating consumers [29]. In our study particularly, web sites scored poorly across multiple questions as they lacked essential information on cannabis topics including risks of treatment, impact on patient quality of life, and uncertainties in research, among others. Moreover, the research of cannabis is arguably an emerging field that has been given considerably more attention over recent years; therefore, clear information on the risks and benefits of its use may not be easily found by many web site owners. Furthermore, web site owners may lack the expertise in interpreting and providing health-related information [30,31,32]. There is also a significant amount of misinformation present online about cannabis [33], and web site owners may also be influenced by this especially if they lack the necessary training to read and interpret the peer-reviewed literature or other sources providing reliable, but complex, information.
Comparative literature
This is the first study to broadly evaluate the quality of health information provided by online cannabis vendors selling to Canadian consumers, with no restrictions on health conditions or purpose of use. Ng et al. recently used the DISCERN instrument to evaluate the quality of web-based consumer health information at the intersection of cannabis and pain [34]. Although the averaged DISCERN scores were found to be higher than those in our study, the quality of health information in this area was still concluded to be poor. Considering that cannabis is commonly used by consumers for a wide range of conditions other than pain, it is important to broadly evaluate the quality of consumer health information without excluding other diseases/conditions. Additionally, that study included health portal, professional, cannabis news, non-profit, and commercial web sites from the Netherlands, the United States, and Canada, whereas our focus was specifically on commercial web sites selling cannabis products to Canadian consumers.
Similar studies have been conducted in jurisdictions other than Canada, primarily in the United States. In 2014, Boatwright et al. evaluated the quality of medical marijuana claims on popular web sites determined by online marketing tools, in which they found that 76% of claims made by web sites were inaccurate and were based on low-quality evidence [35]. In comparison to the objectives of the present study, Boatwright et al., evaluated the accuracy and quality of only three medical cannabis claims on each web site, as opposed to assessing the entire web site. Three other studies from the United States (Luc et al., Cavazos-Rehg et al., and Kurger et al.) analyzed the content provided by online cannabis retailers, and concluded that many dispensaries made unsubstantiated claims about the benefits of cannabis for various conditions, such as nausea, depression, and anxiety [36,37,38]. Aligning with the findings from our study, Luc et al. and Kruger et al. also reported that there was limited mention of potential side effects or risks associated with cannabis use [36, 38]. Moreover, a study from the United Kingdom found that much of the online information about medical cannabis would raise unrealistic expectations of benefits and downplay potential side effects [26]. In agreement with this finding, one study noted that these effects were magnified by commercial web sites compared to other sources of online information (e.g., government, health portal, non-profit), indicating the biases associated with commercial interests [26]. Across other forms of media such as news outlets and online discussion forums, the quality and accuracy of cannabis-related health information, as well as reporting of risks, was also found to be poor [26, 39,40,41]. It is worth mentioning that these aforementioned studies did not use the DISCERN instrument, which in addition to quality, assesses the reliability of consumer health information, as opposed to accuracy.
Implications and future directions
The low quality of health information provided by online cannabis vendors poses potential health risks to consumers. We found that crucial information such as warnings, adverse effects, and/or contraindications associated with the use of cannabis was lacking on many web sites. In addition to this, studies conducted in other jurisdictions suggest that many of the online health claims surrounding cannabis are either unsubstantiated, low in accuracy, and/or derived from a low level of evidence [35,36,37,38,39,40]. Together, these may lead to the misuse of cannabis and have major safety implications for consumers. Currently, promotions prohibitions exist under the Cannabis Act and Cannabis Regulations wherebystate that cannabis or cannabis products “cannot be promoted in a manner that is false, misleading or deceptive or that is likely to create an erroneous impression about its characteristics, value, quantity, composition, strength, concentration, potency, purity, quality, merit, safety, health effects or health risks” [42]. Despite this, many online vendorsappear to not abide by these standards.
Patients may bring up their interest in or their use of cannabis to HCPs, who should be aware of the low quality of cannabis-related health information provided by online vendors as highlighted by our findings. HCPs should appropriately caution patients about these findings and refer them to sources of high-quality information, such as the National Center for Complementary and Integrative Health [43]. This will ensure that patients are adequately informed prior to purchasing cannabis online and may ultimately guide purchasing and using behaviors. Unfortunately, another concern relates to HCPs’ training and education on the topic of cannabis, both in Canada and across other jurisdictions. As many HCPs lack the necessary knowledge to effectively counsel patients about the safe use of cannabis, they are often reluctant to discuss this as a therapeutic option with patients [44,45,46]. With the known and rapid increase in cannabis vendors and the low-quality information provided by them online, it is of urgent importance to adequately train HCPs and HCP students so that patients have a reliable provider of information to turn to for guidance. Public health agencies and those involved in cannabis-specific health policy may consider using the present study as a resource to inform HCPs and patients alike of the high likelihood of low-quality information being provided by online cannabis vendors.
Although our study evaluated the quality of cannabis-related health information provided by vendors that ship to Canada, and similar research has been conducted in the United States, it would be beneficial for further research to replicate this study in other jurisdictions where cannabis has been legalized in a similar manner, such as South Africa [47]. Moreover, one study identified that source credibility had no significant effect on consumers’ interpretation of the quality of online health information [48]. Future research should also evaluate the accuracy of information provided by online cannabis vendors, similar to the approach used by Boatwright et al. for medical cannabis, as this was not possible using the DISCERN instrument [35]. When doing this, a special focus should be placed on distinguishing between the type of sources used to support information (e.g., peer-reviewed literature versus blog posts written by non-experts), allowing for low-quality information and inaccuracies to be identified. Lastly, one study examined the implementation and effectiveness of online responsible vendor training for recreational marijuana in the United States, revealing that most employees were satisfied with the training and found it user-friendly [49]. Although this training was mainly focused on regulatory practices such as using the state’s inventory tracking system or checking for valid identifications, the authors suggest that cannabis-specific training on topics such as safety and dosing is a crucial future step. Such training may be beneficial for owners of online cannabis vendors in Canada as well as other jurisdictions, allowing them to incorporate important topics related to cannabis safety in online descriptions, thus research evaluating the effectiveness of such training would be of value. Lastly, the extent to which information provided online by vendors may influence consumers’ choice and usage behaviors of cannabis products is not well understood [36]. It is possible that misleading or inaccurate descriptions may cause consumers to misuse products in ways that may pose significant health risks. Therefore, future research should serve to study whether online cannabis information may have such effects on consumers.
Strengths and limitations
One strength of the present study included the use of a validated and reliable instrument, DISCERN, to assess the quality of consumer health information about cannabis products. Another strength was the use of six different search terms on Google.ca, of which the first 40 search results were viewed for each (totaling 240 webpages), ensuring that the most frequently visited online cannabis vendors were captured and assessed. To our knowledge, this study is the first to assess the quality of health information provided by online cannabis vendors in Canada, with no restrictions to information on certain medical conditions.
One limitation to our methodology was that only web sites with English-language content were eligible, potentially excluding web sites in French (Canada’s second national language), among other languages. Additionally, considering that the Internet is constantly changing, we acknowledge that we only identified and assessed web sites at a certain snapshot of time. Therefore, if our study was replicated in the future, the content on many of these web sites may have changed, and different web sites (and the quality of information they provide) may appear in the search results. Further, an inherent limitation of the DISCERN tool is that while it can be used to assess whether references and additional sources of information are provided by web sites, it does not distinguish between the types of sources, such as peer-reviewed scientific literature versus blog posts, where the former would be deemed more credible in most cases and increase the quality of the information provided by the web site.