Notably, as commonly seen with other CM studies, patients ultimately earned approximately 50-60% of the maximum amount available in prizes in the $560 condition but only approximately 25-30% of the maximum amount available in prizes in the $250 condition = 14.52, p <.001. This and other studies examining the effect of the magnitude of rewards on outcomes suggest that value matters but only to a certain amount, at which point the relative benefit plateaus and patients ultimately around 60% of the total amount offered .Approximately, 23–56% of HIV+ individuals report using marijuana to alleviate disease-related symptoms and medication side effects , indicating potential benefits of MJ. However, the cognitive consequences remain highly debated . Some studies of healthy populations have not found adverse cognitive effects following abstinence , whereas others have reported acute as well as long-term effects on cognition when compared to non-users . Furthermore, animal studies of Alzheimer’s disease and neuroin- flammation-induced cognitive damage support the neuro protective effects of cannabinoids . While the adverse effects of MJ on cognitive functioning are still unclear, HIV-associated cognitive compromise is well-documented . However, few investigations have examined the interactive effects of MJ and HIV status on cognitive functioning. One study found that self-reported frequent MJ use was associated with greater memory impairment, but only among symptomatic patients . Chang and colleagues found no additive effects on a measure of reaction time, a finding that was attributed to the relatively asymptomatic status of the HIV+ sample. For the current study, we examined the combined effects of HIV status and MJ use on neurocognitive and immune functioning among a sample with varying degrees of use.The current study found main effects for both HIV status and MJ use on neurocognitive functioning. HIV+ moderate-to-heavy users performed significantly worse on learning/memory than other comparison groups, vertical grow shelf whereas HIV+ light users performed significantly better on verbal fluency than HIV– light users.
HIV+ MJ users evidenced higher plasma CD4 and lower viral load than HIV+ non-users, suggesting healthier immune functioning. This is consistent with a recent investigation by Costantino et al. that found a 40% reduction in HIV-1-infected CD4+ cells that were pre-treated with a cannabinoid receptor 2 agonist. Nevertheless, there was a trend for moderate-to-heavy MJ use to be associated with worse performance on cognitive functioning for HIV+ and HIV– individuals, which is consistent with previous reports . Light users on average demonstrated better performance than heavy users, but it is unclear why HIV+ light users outperformed HIV– light users in the domain of verbal fluency. We should note that although the performance differences were statistically significant, froma clinical standpoint, the scores obtained from the HIV+ light users and HIV– light users fall well within the average range. These results highlight the complex relationship between MJ use and neurocognitive functioning as a function of chronic disease. If light or occasional MJ use protects against disease progression or helps with maintaining adequate immune functioning without associated cognitive compromise, such use may have a neuroprotective role in several neuroinflammation related diseases . However, the mechanisms by which MJ act upon immune and neurocognitive functioning cannot be determined from the current study. Further, our sample was from a region that has legalized the use of medical MJ. Perhaps there is more variability in the sources and preparations of MJ used among our sample in comparison to prohibited areas. Finally, we were unable to gather information about age of onset of MJ use and our abstinence period was very short . This limits our interpretation as we cannot determine if moderate-to-heavy smokers performed worse on cognitive testing as a function of starting at an earlier age, or if the observed effects would remain after a prolonged period of abstinence. In a previous study, we found that individuals who abstained from smoking cannabis for four weeks continued to demonstrate deficits in executive functioning, although most other performances were similar to non-users . In sum, based on the needs of this population and the rapidly advancing legislation of medicinal cannabis use, there is a pressing need for future investigations to isolate the benefits for medicinal purposes. There is a mix of low-quality and moderate-quality evidence supporting the therapeutic effects of cannabinoids across clinical trials .
As more studies adhere to CONSORT guidelines, appropriate dosage levels , formulations, and delivery mechanisms may be established.Following recreational marijuana legalization and commercialization in the US, marijuana dispensaries have served as a major venue for marijuana retail sales in neighborhoods. Nonetheless, research on the impacts of marijuana dispensaries on public health remains limited . Availability, accessibility, and point-of-sale marketing of retail outlets have been associated with attitudes, perceptions, and health behaviors in tobacco and alcohol literature . Marijuana dispensaries may impact marijuana-related outcomes in a similar manner. They may increase availability and accessibility of marijuana , promote greater awareness and consumption through marketing activities , increase product appeal such as through increased quality and potency , diversify product variation such as vaping devices and edibles , reduce prices through mass production and introduction of competition , and shape social norms favorable of marijuana use . A major challenge in understanding the availability and retail environments of marijuana dispensaries is identifying a complete and accurate list of marijuana dispensaries in neighborhoods. In a state operating a statewide licensing system, one can obtain the official licensing directories from government databases. Nonetheless, most of these directories are updated infrequently. More importantly, they do not reflect the operation status of dispensaries in reality or capture unlicensed dispensaries that are common in areas with weak law enforcement. Business directories provided by commercial providers are commonly used to identify tobacco, alcohol, and food retail outlets when state licensing directories are unavailable or unsatisfactory . Unfortunately, these commercial databases had not systematically gathered information on marijuana dispensaries by the time of this study. One can also conduct a field census with direct search and observation to enumerate a certain type of business in a geographic area. It is considered to be the best practice in outlet identification and often used to validate the business lists obtained from commercial databases . The limitation of field census is obvious: the required efforts and resources increase exponentially as the geographic area of interest expands. Due to practical and budget concerns, most tobacco, alcohol, and food outlet studies that adopted this method searched retail outlets in smaller regions such as a county. State-level field censuses, especially in a large state like California, are nearly nonexistent.
In light of the challenges of using conventional approaches to identify marijuana dispensaries, existing studies have primarily relied upon a single or a few online crowd sourcing platforms, such as Weed maps, Leafly, and Yelp, to obtain dispensary information voluntarily submitted by dispensary owners and marijuana users . Because these platforms serve as online communities to promote dispensaries, products, and share experiences, they are perceived to be more up-to-date and comprehensive than official licensing directories. Particularly, these platforms provide data on both licensed and unlicensed dispensaries. Despite the increasingly common use of online crowd sourcing platforms in marijuana research, the validity of this approach has not been comprehensively assessed at statewide level. To date, only two studies have conducted validation in a single county , one before recreational marijuana commercialization and one after the commercialization in California. In this study, we examined the validity of using secondary data sources, including the state licensing directory and commonly used online crowd sourcing platforms, in enumerating brick-and-mortar marijuana dispensaries across the entire state of California.In November 2016 California legalized recreational marijuana and in January 2018 California initiated retail sale of recreational marijuana in dispensaries. California now has the largest legal marijuana market in the world, with sales rising from $2.5 billion in 2018 to $3.1 billion in 2019 . Although California allows delivery services, in this study, we concentrated only on brick-and-mortar marijuana dispensaries because delivery-only providers do not have storefronts to showcase and promote products. In addition, the wide geographic coverage of delivery services contributes little variation in marijuana availability at neighborhood level. We offered a protocol for identifying dispensaries that can be replicated in other large geographic regions with marijuana retail sales. We aimed to answer two research questions. The first question was to what extent online crowd sourcing platforms are valid in enumerating licensed brick-and-mortar dispensaries. The motivation was that many dispensaries in California operated without a license. Even for licensed dispensaries, how they operate in practice may not agree with what was approved in the license. Findings from the first question will provide quantifiable evidence on the level of agreement between state licensing directory and online crowd sourcing platforms,cannabis grow indoor add surveillance data point on the operation of unlicensed dispensaries, and inform policymakers regarding the validity of using online crowd sourcing platforms as alternatives when state licensing directory is not publicly accessible or licensing information is inadequate.
The second question was to what extent state licensing directory and online crowd sourcing platforms are valid in enumerating the universe of active brick-and-mortar dispensaries. The motivation was that a single data source may not capture all active dispensaries in California and the information in a data source may not agree with how dispensaries operate in practice. Findings from the second question will provide quantifiable evidence on the strengths and weaknesses of each data source, inform surveillance and research regarding how to best strategize data use when resources are limited, and demonstrate the need for combining multiple data sources and verifying information to obtain the universe of dispensaries in a large geographic area. Because recreational-only, medical-only, and recreational & medical dispensaries co-existed in California, we also assessed validity measures by dispensary category. Dispensaries may tend to promote themselves on online crowd sourcing platforms in larger counties with keen competition, we hence further assessed validity measures by county population size. In May 2019, we obtained marijuana business lists from multiple secondary data sources: 1) the state official licensing directory was obtained from the California Bureau of Cannabis Control online license search portal, and 2) business directories were obtained from three commonly used online crowd sourcing platforms, including Weed maps, Leafly, and Yelp. Weed maps and Leafly specialize in marijuana business listings, whereas Yelp provides general business listings encompassing various types of industries. Key words “marijuana”, “weed”, “cannabis”, and “dispensary” that were commonly used in Yelp to describe marijuana-related businesses were used to search records on Yelp. All four secondary data sources contained information on business name, street address, phone number, and delivery services, but dispensary category was only available on BCC, Weed maps, and Leafly. Because business listings included both delivery services and brick-and-mortar dispensaries, we first removed businesses if the online information indicated that they only provided delivery services without storefronts. We then removed duplicated records by hand if two or more dispensaries within a single data source had the same business name and street address. We further combined records from all four data sources and removed duplicated records across data sources. The cleaned, combined database included 2,121 unique businesses .From May to July 2019, eight trained research associates aged 21 or older called the 2,121 unique businesses to verify their street address, operation status, category of business, and presence of storefronts . Each call took fewer than 5 minutes on average. As commonly done in compliance check inspections of tobacco product retailers, the research associates did not reveal the research purpose of the calls. Instead, they identified themselves as interested customers who were considering a visit in near future. To determine dispensary category, researchers asked if a doctor’s recommendation or a patient registration card was required to enter the dispensary and make purchase. An affirmative response indicated the dispensary category to be medical only. If the response was negative yet customers with a doctor’s recommendation or a patient registration card were eligible for reduced tax rates, the dispensary was categorized as recreational & medical. The remaining dispensaries were considered to be recreational only. Up to five calls were made to each business in different business hours and/or on different business days to determine operation status. If a dispensary could not be reached after five call attempts, researchers checked its recent online activities on Weed maps, Leafly, Yelp, and Google Map Reviews.