<Table 3. Summary of Findings by Period >
Citing articles from the first period (1986-1996) expressed concern at the lack of scientific evidence for long-term opioid prescribing. The articles published in this period were more accurate and affirmational than the two subsequent periods. Compared to later interpretations of the index study, these more accurately represented the actual conclusions and prescribing guidance proposed by Portenoy and Foley. This was a period of exploration with a focus on increasing the amount of evidence for opioid prescribing for chronic non-cancer pain.
However, this period of exploration concluded at our identified breakpoint in 1997. Just a year before, OxyContin® was approved in the United States, a drug that would go on to define the early American opioid crisis. What had been a period of exploration quickly transitioned into a period of implementation during which sales of OxyContin® skyrocketed from $48M USD in 1996 to $1.1B in 2000.42In this second period (1997-2003), the proportion of empirical articles reached its highest peak of the three periods. At first glance, this signifies that concerns about the need for more scientific evidence for opioids from the first period were being addressed. However, our qualitative analysis suggests that this empirical research focused mostly on the efficacy of short-term opioid use, rather than providing details about long-term effects, either negative or positive. This was coupled with a rise in inaccurate citations demonstrating that interpretations began to stray further from the substance of the index study. In the first exploration period, the index study was being accurately cited as impetus to seek more evidence for opioid prescribing, but by this second implementation period it was increasingly being inaccurately cited as evidence in support of regular opioid prescribing.
In other words, a push for increased opioid prescribing altered how scientific evidence was interpreted. In their analysis on the societal embedding of new technologies, Geels et al. write that “innovators, entrepreneurs or health advocates try to attract attention from sponsors and lobby to create a favourable regulatory environment. Product champions make optimistic, but diffuse promises about future performance, societal benefits and profits.”41In this case, the index study was used to make “diffuse promises” that in many cases were inaccurate. This misinterpretation is most obvious in how the index study’s recommendation of interdisciplinary treatment was largely overlooked. While Portenoy and Foley originally noted that opioids should be prescribed as part of an interdisciplinary treatment plan with the “concurrent use of ancillary cognitive/behavioural and physical therapies,” the promised benefits of opioids quickly overshadowed this recommendation. According to Bernard et al., “what was intended to be multimodal care, however, became unidimensional care in most settings with reliance almost completely on pharmacologic solutions to pain.”43The prospect of opioids as a one-step solution for chronic pain prompted governmental and non-governmental organizations to make opioids more accessible for chronic non-cancer pain.43This second period showed an increasingly liberal and often inaccurate interpretation that was associated with increasing opioid-related harms.
Between 2004 and 2019, opioid-related harms increasingly permeated North American society. Whereas the previous periods explored and implemented opioids as a solution for chronic pain, this latter period has been one of concern and reassessment . The number of papers that attributed the opioid crisis to the index study grew exponentially. Negative citations also grew significantly, making this by far the most negational period. As opioids drew more ire from the scientific community, so too did the index study. This tracks with Geels’ model that the “peak of inflated expectations” is often followed by a trough of disillusionment in which “there are some successes with the new technology, but more failures.”41This process is exemplified by yet another rise in inaccurate citations in the third period. However, these now grew alongside attributive and negational citations. Whereas earlier inaccurate citations were affirmational and encouraged liberal opioid prescribing practices, these later inaccurate citations were negational and misinterpreted the index study as having been a carte blanche for opioid prescribing that incited the crisis.