TABLE 4.

Future research agenda and research questions.

Drivers	Concepts/theories	Potential research questions
Risk	Perceived risk	How do differences in the degree of risk across specific medications, dosages, and efficacies impact consumers’ intentions to purchase online or their actual purchase behavior?
		To what degree do consumers perceive online purchases of medicine to involve different types of risk (e.g., financial or physical)? How much financial risk do they perceive and why (e.g., fraudulent charges after online medicine purchases or waste of money on ineffectual/fake drugs)? How much physical risk do they perceive and why (e.g., fake medicine purchased online harms health or is adulterated with opioids leading to addiction)? How much source risk do consumers perceive and why (e.g., personal information for online medication purchase used in spam emails/calls, invasion of privacy, or identity theft)?
		What is the nature and prevalence of adverse effects suffered by consumers who purchase medicine online? Does it differ across types of online pharmacies (e.g., chain, independent, and cost-plus legitimate pharmacies versus rogue/illicit pharmacies)?
	Uncertainty avoidance	How do consumers attempt to manage the risk of online medical purchases?
		How can public policymakers highlight the risks of illicit or rogue pharmacies in educational campaigns to decrease consumer purchases?
	Decision-making heuristics	What heuristics and cues do consumers use to identify “safe” online medicine sources for purchase? Are these heuristics and cues accurate?
	Regulatory focus theory	What risks do medicine purchases online pose to healthcare providers? How prepared are they to address these risks, and how can educators better prepare medical and pharmaceutical students to better address the risks as future healthcare practitioners who are involved in monitoring and discussing online sources of medicine with patients?
		How do consumers’ online medication purchase intentions and behavior differ if they are primarily prevention-focused (focused on avoiding losses) or promotion-focused (focused on seeking gains)?
Benefits	Manifest and latent motives	How do the manifest motives (benefits that consumers freely admit seeking) differ from the latent motives (those that consumers do not want to admit or reveal to others) for online medication purchases?
	Benefits segmentation	How are consumers’ online medicine purchase intentions and behavior impacted by the specific benefit sought (e.g., perceived anonymity, avoidance of embarrassment, cost savings, improved availability, greater autonomy, ability to self-diagnose/self-medicate, greater access, delivery to remote areas, or off-label usage)? How can traditional brick-and-mortar or legitimate online pharmacies better incorporate these benefits, and would doing so reduce consumer purchases from illicit online pharmacies? To what extent do consumers intend to purchase or purchase medicine specifically from illicit online pharmacies to seek these perceived benefits?
	Product features, attributes, and benefits	What benefits do consumers believe online medical purchases offer based on online pharmacies’ features and tangible attributes?
		How have closures of locations of large chain pharmacies (e.g., Rite-Aid and Walgreens) impacted consumers’ perceptions of online pharmacies offering benefits related to availability and convenience? Have such closures increased purchases from legitimate and illicit online pharmacies?
Learning	Information processing	How is the proportion of consumers who intend to or have purchased medicine online affected by the degree of awareness of online sources of medicine or by information about them stored in memory?
		What types of information increase versus overcome consumer resistance to purchasing medications online?
		How can education campaigns best model the dangers of illicit online pharmacies to discourage consumer purchases from them?
		How does providing information about online pharmacies, their risks, or benefits by public health officials in public service advertising campaigns impact consumer purchase intentions and behavior?
	Vicarious learning/modelling	How and to what extent does exposure to other consumers’ ratings and reviews available on online pharmacies impact consumer purchase intentions and behavior? How do these consumer ratings and reviews compare to healthcare providers’ professional opinions regarding outcomes, such as efficacy or side effects?
	Cognitive learning	What beliefs do consumers form based on exposure to other consumers’ ratings and reviews versus FDA-approved patient labeling?
		What types of information do healthcare providers communicate about purchasing medications online? How does this impact consumer beliefs, attitudes, and purchase intentions? What information would consumers find most useful to optimize purchase decisions?
	Cognitive capacity	Consumers’ cognitive resources are limited; how does this impact their acquisition and retention of information from various sources (e.g., healthcare providers, FDA-approved patient labeling, or online ratings and reviews) and subsequent purchase intentions and behavior?
	Perceptual fluency	Does making information presented by an online pharmacy easier to process and comprehend (e.g., bullet points versus paragraphs) increase purchase intentions and behavior toward that online pharmacy’s medications?
Search	External information search	Is there an inverse relationship between the amount of physician-provided information and online information search? What is the effect of each on online purchase intentions and behavior?
		Does the information provided in direct-to-consumer advertising encourage more extensive information searches and greater online purchase intentions and behavior? How does the effect differ between targeted consumers versus the unintended audience also exposed to the message, but with less medical need for the advertised drug?
		To what degree are expatriates likely to seek information about and purchase medicines from their home country versus their country of settlement? How does this impact online medical sales? What methods do expatriates use to locate and purchase medicines online from their home country?
	Involvement/personal relevance	Greater involvement should increase information search as consumers attempt to improve purchase decision quality for more personally relevant decisions. Do the greater health consequences and costs of prescription than OTC medications increase involvement and, hence, information search? How does that affect the amount and type of information that consumers seek when making purchase decisions for a prescription versus an OTC medication?
	Intrinsic versus extrinsic motivation	Do chronic conditions, due to their ongoing nature, increase enduring involvement and, hence, search for information regarding online medicine purchases compared to acute conditions?
		To what degree do those with chronic diseases prefer to purchase medication online compared to healthy consumers or those with acute conditions? Does the greater frequency of purchasing, the cumulative cost, the difficulty traveling to or navigating a brick-and-mortar pharmacy, or some other factor mediate the relationship between chronic conditions and the greater likelihood of purchasing medications from online sources?
	Search engine optimization Search engine marketing	How can legitimate online pharmacies and brick-and-mortar pharmacies better use search engine optimization and search engine marketing to encourage consumers to switch medication purchases from rogue sites to these legal sellers?
Situational influences	Communication situation	To what degree do consumers intend to or purchase medications via illicit online pharmacies following exposure to direct-to-consumer advertising? Do they first ask their physician for the advertised medication? If so, does a physician’s refusal to prescribe increase or decrease consumers’ likelihood of purchasing the advertised medication online?
	Purchase situation	Does direct-to-consumer advertising of prescription medication impact online purchase intentions or behavior? Is the effect greater among consumer groups with fewer resources (e.g., financial resources or cognitive resources) or among vulnerable populations?
		What is the relationship between online medicine purchases and cross-border sales of medicine? To what degree do consumers travel to purchase medicine or receive medical care versus purchase medications online? What accounts for this behavior (e.g., immigration status, living in a borderland region, or medication availability or cost in the country of residence)? What leads consumers to choose online over cross-border medication purchases?
	Usage situation	Are consumers without health insurance more likely to purchase from online pharmacies? If so, how can healthcare providers and public policymakers encourage purchases from legitimate rather than illicit online sources? Comparatively, how effective are different types of interventions (e.g., educational materials, lists of legitimate sources, healthcare provider recommendations)?
	Temporal perspective	How does perceived time pressure impact consumers’ purchase intentions and behavior toward online versus brick-and-mortar pharmacies?
	Cognitive tax	How do situations that introduce cognitive taxes, which reduce a consumer’s cognitive capacity remaining for decision-making (e.g., poverty or illness), impact intentions and behavior toward online pharmacies, especially illicit ones that do not require prescriptions?
Familiarity	Prior experience	How does familiarity with purchasing other products online affect online medication purchase intentions and behavior? Do online medication purchase intentions and behavior differ depending on the types of products frequently purchased online?
	Consumer expertise	How does familiarity with a brick-and-mortar chain or independent pharmacy affect consumer purchase intentions and behavior toward an affiliated online pharmacy?
	Objective and subjective knowledge	Does trust, satisfaction with prior purchases, or liking mediate the relationship between online pharmacy familiarity and purchase intentions or behavior?
	Mere exposure	The Enrichment Hypothesis holds that increasing product experience develops consumers’ ability to attend to and retain relevant information about that product. How does familiarity-enhanced attention to and memory for relevant product information affect online medication purchase intentions and behavior? Does greater prior experience alter the distribution of consumers purchasing from legitimate versus illicit online pharmacies?
	Enrichment Hypothesis
Trust	Skepticism	How do consultations with physicians and pharmacists associated with online pharmacies impact consumer trust and skepticism toward online pharmacies or purchase intentions and behavior? Does the modality of the consultation (e.g., email exchange, chat, or video conference) affect these relationships?
		How do shortages and supply chain disruptions affect online purchase intentions and behavior? Do consumers view online access to be sufficiently beneficial to overcome skepticism toward and build trust in online pharmacies, even illicit online sources?
Post-purchase evaluations	Customer satisfaction versus dissatisfaction	Are consumers satisfied or dissatisfied with their online pharmacy purchases?
		How satisfied are consumers with the purchase process and the medications received following an online medication purchase?
		Does the degree of satisfaction differ across types of sources for online medication purchases (e.g., legitimate vs. illicit online pharmacy, cost-plus or traditional online pharmacy, chain or independent online pharmacy)?
	Postpurchase dissonance	What impact does post-purchase evaluation have on future purchase intentions and subsequent purchase behavior?
		How common is postpurchase dissonance following an online medication purchase? How does it affect future purchase intentions and behavior toward online pharmacies?