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Serial position scores on verbal memory tests are sensitive to early Alzheimer’s disease (AD)-related neuropathological changes that occur in the entorhinal cortex and hippocampus. The current study examines longitudinal change in serial position scores as markers of subtle cognitive decline in older adults who may be in preclinical or at-risk states for AD.
This study uses longitudinal data from the Religious Orders Study and the Rush Memory and Aging Project. Participants (n = 141) were included if they did not have dementia at enrollment, completed follow-up assessments, and died and were classified as Braak stage I or II. Memory tests were used to calculate serial position (primacy, recency), total recall, and episodic memory composite scores. A neuropathological evaluation quantified AD, vascular, and Lewy body pathologies. Mixed effects models were used to examine change in memory scores. Neuropathologies and covariates (age, sex, education, APOE e4) were examined as moderators.
Primacy scores declined (β = −.032, p < .001), whereas recency scores increased (β = .021, p = .012). No change was observed in standard memory measures. Greater neurofibrillary tangle density and atherosclerosis explained 10.4% of the variance in primacy decline. Neuropathologies were not associated with recency change.
In older adults with hippocampal neuropathologies, primacy score decline may be a sensitive marker of early AD-related changes. Tangle density and atherosclerosis had additive effects on decline. Recency improvement may reflect a compensatory mechanism. Monitoring for changes in serial position scores may be a useful in vivo method of tracking incipient AD.
The Hierarchical Taxonomy of Psychopathology (HiTOP) has emerged out of the quantitative approach to psychiatric nosology. This approach identifies psychopathology constructs based on patterns of co-variation among signs and symptoms. The initial HiTOP model, which was published in 2017, is based on a large literature that spans decades of research. HiTOP is a living model that undergoes revision as new data become available. Here we discuss advantages and practical considerations of using this system in psychiatric practice and research. We especially highlight limitations of HiTOP and ongoing efforts to address them. We describe differences and similarities between HiTOP and existing diagnostic systems. Next, we review the types of evidence that informed development of HiTOP, including populations in which it has been studied and data on its validity. The paper also describes how HiTOP can facilitate research on genetic and environmental causes of psychopathology as well as the search for neurobiologic mechanisms and novel treatments. Furthermore, we consider implications for public health programs and prevention of mental disorders. We also review data on clinical utility and illustrate clinical application of HiTOP. Importantly, the model is based on measures and practices that are already used widely in clinical settings. HiTOP offers a way to organize and formalize these techniques. This model already can contribute to progress in psychiatry and complement traditional nosologies. Moreover, HiTOP seeks to facilitate research on linkages between phenotypes and biological processes, which may enable construction of a system that encompasses both biomarkers and precise clinical description.
Virtual reality has emerged as a unique educational modality for medical trainees. However, incorporation of virtual reality curricula into formal training programmes has been limited. We describe a multi-centre effort to develop, implement, and evaluate the efficacy of a virtual reality curriculum for residents participating in paediatric cardiology rotations.
A virtual reality software program (“The Stanford Virtual Heart”) was utilised. Users are placed “inside the heart” and explore non-traditional views of cardiac anatomy. Modules for six common congenital heart lesions were developed, including narrative scripts. A prospective case–control study was performed involving three large paediatric residency programmes. From July 2018 to June 2019, trainees participating in an outpatient cardiology rotation completed a 27-question, validated assessment tool. From July 2019 to February 2020, trainees completed the virtual reality curriculum and assessment tool during their cardiology rotation. Qualitative feedback on the virtual reality experience was also gathered. Intervention and control group performances were compared using univariate analyses.
There were 80 trainees in the control group and 52 in the intervention group. Trainees in the intervention group achieved higher scores on the assessment (20.4 ± 2.9 versus 18.8 ± 3.8 out of 27 questions answered correctly, p = 0.01). Further analysis showed significant improvement in the intervention group for questions specifically testing visuospatial concepts. In total, 100% of users recommended integration of the programme into the residency curriculum.
Virtual reality is an effective and well-received adjunct to clinical curricula for residents participating in paediatric cardiology rotations. Our results support continued virtual reality use and expansion to include other trainees.
Understanding how cardiovascular structure and physiology guide management is critically important in paediatric cardiology. However, few validated educational tools are available to assess trainee knowledge. To address this deficit, paediatric cardiologists and fellows from four institutions collaborated to develop a multimedia assessment tool for use with medical students and paediatric residents. This tool was developed in support of a novel 3-dimensional virtual reality curriculum created by our group.
Educational domains were identified, and questions were iteratively developed by a group of clinicians from multiple centres to assess understanding of key concepts. To evaluate content validity, content experts completed the assessment and reviewed items, rating item relevance to educational domains using a 4-point Likert scale. An item-level content validity index was calculated for each question, and a scale-level content validity index was calculated for the assessment tool, with scores of ≥0.78 and ≥0.90, respectively, representing excellent content validity.
The mean content expert assessment score was 92% (range 88–97%). Two questions yielded ≤50% correct content expert answers. The item-level content validity index for 29 out of 32 questions was ≥0.78, and the scale-level content validity index was 0.92. Qualitative feedback included suggestions for future improvement. Questions with ≤50% content expert agreement and item-level content validity index scores <0.78 were removed, yielding a 27-question assessment tool.
We describe a multi-centre effort to create and validate a multimedia assessment tool which may be implemented within paediatric trainee cardiology curricula. Future efforts may focus on content refinement and expansion to include additional educational domains.
Young people with social disability and severe and complex mental health problems have poor outcomes, frequently struggling with treatment access and engagement. Outcomes may be improved by enhancing care and providing targeted psychological or psychosocial intervention.
We aimed to test the hypothesis that adding social recovery therapy (SRT) to enhanced standard care (ESC) would improve social recovery compared with ESC alone.
A pragmatic, assessor-masked, randomised controlled trial (PRODIGY: ISRCTN47998710) was conducted in three UK centres. Participants (n = 270) were aged 16–25 years, with persistent social disability, defined as under 30 hours of structured activity per week, social impairment for at least 6 months and severe and complex mental health problems. Participants were randomised to ESC alone or SRT plus ESC. SRT was an individual psychosocial therapy delivered over 9 months. The primary outcome was time spent in structured activity 15 months post-randomisation.
We randomised 132 participants to SRT plus ESC and 138 to ESC alone. Mean weekly hours in structured activity at 15 months increased by 11.1 h for SRT plus ESC (mean 22.4, s.d. = 21.4) and 16.6 h for ESC alone (mean 27.7, s.d. = 26.5). There was no significant difference between arms; treatment effect was −4.44 (95% CI −10.19 to 1.31, P = 0.13). Missingness was consistently greater in the ESC alone arm.
We found no evidence for the superiority of SRT as an adjunct to ESC. Participants in both arms made large, clinically significant improvements on all outcomes. When providing comprehensive evidence-based standard care, there are no additional gains by providing specialised SRT. Optimising standard care to ensure targeted delivery of existing interventions may further improve outcomes.
Early in the COVID-19 pandemic, the World Health Organization stressed the importance of daily clinical assessments of infected patients, yet current approaches frequently consider cross-sectional timepoints, cumulative summary measures, or time-to-event analyses. Statistical methods are available that make use of the rich information content of longitudinal assessments. We demonstrate the use of a multistate transition model to assess the dynamic nature of COVID-19-associated critical illness using daily evaluations of COVID-19 patients from 9 academic hospitals. We describe the accessibility and utility of methods that consider the clinical trajectory of critically ill COVID-19 patients.
The end-Cretaceous (K/Pg) mass extinction event is the most recent and well-understood of the “big five” and triggered establishment of modern terrestrial ecosystem structure. Despite the depth of research into this event, our knowledge of upper Maastrichtian terrestrial deposits globally relies primarily on assemblage-level data limited to a few well-sampled formations in North America, the Hell Creek and Lance Formations. These assemblages disproportionally affect our interpretations of this important interval. Multiple investigations have quantified diversity patterns within these assemblages, but the potential effect of formation-level size-dependent taphonomic biases and their implications on extinction dynamics remains unexplored. Here, the relationship between taphonomy and body size of the Hell Creek Formation and Lance Formation dinosaurs and mammals are quantitatively analyzed. Small-bodied dinosaur taxa (<70 kg) are consistently less complete, unlikely to be articulated, and delayed in their description relative to their large-bodied counterparts. Family-level abundance (particularly skeletons) is strongly tied to body mass, and the relative abundance of juveniles of large-bodied taxa similarly is underrepresented. Mammals show similar but nonsignificant trends. The results are remarkably similar to those from the Campanian-aged Dinosaur Park Formation, suggesting a widespread strong taphonomic bias against the preservation of small taxa, which will result in their seemingly depauperate diversity within the assemblage. This taphonomically skewed view of diversity and abundance of small-bodied taxa amid our best late Maastrichtian samples has significant implications for understanding speciation and extinction dynamics (e.g., size-dependent extinction selectivity) across the K/Pg boundary.
To test the hypothesis that higher level of purpose in life is associated with lower likelihood of dementia and mild cognitive impairment (MCI) in older Brazilians.
As part of the Pathology, Alzheimer’s and Related Dementias Study (PARDoS), informants of 1,514 older deceased Brazilians underwent a uniform structured interview. The informant interview included demographic data, the Clinical Dementia Rating scale to diagnose dementia and MCI, the National Institute of Mental Health Diagnostic Interview Schedule for depression, and a 6-item measure of purpose in life, a component of well-being.
Purpose scores ranged from 1.5 to 5.0 with higher values indicating higher levels of purpose. On the Clinical Dementia Rating Scale, 940 persons (62.1%) had no cognitive impairment, 121 (8.0%) had MCI, and 453 (29.9%) had dementia. In logistic regression models adjusted for age at death, sex, education, and race, higher purpose was associated with lower likelihood of MCI (odds ratio = .58; 95% confidence interval [CI]: .43, .79) and dementia (odds ratio = .49, 95% CI: .41, .59). Results were comparable after adjusting for depression (identified in 161 [10.6%]). Neither race nor education modified the association of purpose with cognitive diagnoses.
Higher purpose in life is associated with lower likelihood of MCI and dementia in older black and white Brazilians.
Introduced mammalian predators are responsible for the decline and extinction of many native species, with rats (genus Rattus) being among the most widespread and damaging invaders worldwide. In a naturally fragmented landscape, we demonstrate the multi-year effectiveness of snap traps in the removal of Rattus rattus and Rattus exulans from lava-surrounded forest fragments ranging in size from <0.1 to >10 ha. Relative to other studies, we observed low levels of fragment recolonization. Larger rats were the first to be trapped, with the average size of trapped rats decreasing over time. Rat removal led to distinct shifts in the foraging height and location of mongooses and mice, emphasizing the need to focus control efforts on multiple invasive species at once. Furthermore, because of a specially designed trap casing, we observed low non-target capture rates, suggesting that on Hawai‘i and similar islands lacking native rodents the risk of killing non-target species in snap traps may be lower than the application of rodenticides, which have the potential to contaminate food webs. These efforts demonstrate that targeted snap-trapping is an effective removal method for invasive rats in fragmented habitats and that, where used, monitoring of recolonization should be included as part of a comprehensive biodiversity management strategy.
Major depressive disorder (MDD) and chronic pain are highly comorbid, and pain symptoms are associated with a poorer response to antidepressant medication treatment. It is unclear whether comorbid pain also is associated with a poorer response to treatment with repetitive transcranial magnetic stimulation (rTMS).
162 MDD subjects received 30 sessions of 10 Hz rTMS treatment administered to the left dorsolateral prefrontal cortex (DLPFC) with depression and pain symptoms measured before and after treatment. For a subset of 96 patients, a resting-state electroencephalogram (EEG) was recorded at baseline. Clinical outcome was compared between subjects with and without comorbid pain, and the relationships among outcome, pain severity, individual peak alpha frequency (PAF), and PAF phase-coherence in the EEG were examined.
64.8% of all subjects reported pain, and both depressive and pain symptoms were significantly reduced after rTMS treatment, irrespective of age or gender. Patients with severe pain were 27% less likely to respond to MDD treatment than pain-free individuals. PAF was positively associated with pain severity. PAF phase-coherence in the somatosensory and default mode networks was significantly lower for MDD subjects with pain who failed to respond to MDD treatment.
Pain symptoms improved after rTMS to left DLPFC in MDD irrespective of age or gender, although the presence of chronic pain symptoms reduced the likelihood of treatment response. Individual PAF and baseline phase-coherence in the sensorimotor and midline regions may represent predictors of rTMS treatment outcome in comorbid pain and MDD.
As part of the Pathology, Alzheimer’s and Related Dementias Study, we conducted uniform structured interviews with knowledgeable informants (72% children) of 1,493 older (age > 65) Brazilian decedents.
The interview included measures of social isolation (number of family and friends in at least monthly contact with decedent), emotional isolation (short form of UCLA Loneliness Scale), and major depression plus the informant portion of the Clinical Dementia Rating Scale to diagnose dementia and its precursor, mild cognitive impairment (MCI).
Decedents had a median social network size of 8.0 (interquartile range = 9.0) and a median loneliness score of 0.0 (interquartile range = 1.0). On the Clinical Dementia Rating Scale, 947 persons had no cognitive impairment, 122 had MCI, and 424 had dementia. In a logistic regression model adjusted for age, education, sex, and race, both smaller network size (odds ratio [OR] = 0.975; 95% confidence interval [CI]: 0.962, 0.989) and higher loneliness (OR = 1.145; 95% CI: 1.060, 1.237) were associated with higher likelihood of dementia. These associations persisted after controlling for depression (present in 10.4%) and did not vary by race. After controlling for depression, neither network size nor loneliness was related to MCI.
Social and emotional isolation are associated with higher likelihood of dementia in older black and white Brazilians.
To prioritise and refine a set of evidence-informed statements into advice messages to promote vegetable liking in early childhood, and to determine applicability for dissemination of advice to relevant audiences.
A nominal group technique (NGT) workshop and a Delphi survey were conducted to prioritise and achieve consensus (≥70 % agreement) on thirty evidence-informed maternal (perinatal and lactation stage), infant (complementary feeding stage) and early years (family diet stage) vegetable-related advice messages. Messages were validated via triangulation analysis against the strength of evidence from an Umbrella review of strategies to increase children’s vegetable liking, and gaps in advice from a Desktop review of vegetable feeding advice.
A purposeful sample of key stakeholders (NGT workshop, n 8 experts; Delphi survey, n 23 end users).
Participant consensus identified the most highly ranked priority messages associated with the strategies of: ‘in-utero exposure’ (perinatal and lactation, n 56 points) and ‘vegetable variety’ (complementary feeding, n 97 points; family diet, n 139 points). Triangulation revealed two strategies (‘repeated exposure’ and ‘variety’) and their associated advice messages suitable for policy and practice, twelve for research and four for food industry.
Supported by national and state feeding guideline documents and resources, the advice messages relating to ‘repeated exposure’ and ‘variety’ to increase vegetable liking can be communicated to families and caregivers by healthcare practitioners. The food industry provides a vehicle for advice promotion and product development. Further research, where stronger evidence is needed, could further inform strategies for policy and practice, and food industry application.
“…the said Pirates becoming Masters of those seas have one after another Risen up like Mushrooms, under the very noses of our said men of Warr, for near nine years together, and we never heard that they took more then two of them in America, while those Vermine have taken deeproot…”
In April 1722, eight bodies hung in chains on the hills surrounding Cape Coast Castle, the British Royal African Company's chief fortification on the Gold Coast (modern-day Ghana) in West Central Africa. The hanged men were members of Bartholomew Roberts’ pirate crew who had plundered numerous ships throughout the Atlantic Ocean before being captured off the West African coast, tried and sentenced to death. The bodies of eight of the fifty-two men executed were then displayed in locations visible to ships passing by the coast in order to serve as a “terror to future depredators of the same class”. The defeat and capture of Roberts’ crew by Royal Navy Captain Chaloner Ogle was one of the most substantial victories against pirates during the surge of Atlantic piracy that occurred between 1716 and 1726. On his return in 1723, Ogle was knighted for his conduct, becoming the first naval captain to receive a title for triumph over pirates.
Ogle's victory is often retold as evidence of British maritime power overcoming Atlantic piracy in the early eighteenth century. As the opening quotation suggests, however, Roberts’ defeat was one of only a handful of naval victories over pirates during the ten-year surge that occurred after 1716. In 1722, it was the only direct success by the British Royal Navy over Atlantic pirates despite the fact that there was an average of twenty-four naval vessels assigned to protect trading vessels against pirates in the Caribbean, North America, West Africa and the Indian Ocean. That same year also witnessed the furnishing of two local vessels from Rhode Island to chase pirates preying on regional trade, while a small sloop was hired by Jamaican planters as a guardship to protect the island's coastal regions from piratical attacks. These activities in distant waters coincided with new anti-piracy legislation in London as the British Parliament attempted to effect change by introducing further regulations on Atlantic maritime activity.
At Cape Coast Castle on the Gold Coast (modern-day Ghana), the Royal African Company's headquarters in West Africa, the captured crew of Bartholomew Roberts’ were tried for piracy in nineteen separate trials occurring between 29 March and 19 April 1722. Of the 243 men captured, 168 faced trial. Seventy-seven were acquitted by evidence that suggested they had been forced on board while fifty-two were hanged. A further twenty were condemned to seven years’ servitude in the Royal African Company's African mines, seventeen were transferred to Marshalsea prison in London and two were respited for additional consideration. The remaining seventy-five captured men – described only as “black men” – were sold into slavery without trial. Roberts and his crew had committed numerous depredations in the Caribbean, Newfoundland, Brazil and Africa, before being defeated near Cape Lopez – in modern-day Gabon – by Captain Chaloner Ogle and the crew of the Royal Navy warship Swallow. This proved to be the most substantial naval victory over pirates between 1716 and 1726, which was emphasised by the knighthood granted to Ogle who became the first naval captain to receive a title for triumph over pirates. While the defeat of Roberts, who died during the engagement, and the capture of his crew is often related as one of the most significant events in the suppression of piracy in the early eighteenth century, the role of the British slave trading lobby in facilitating this victory is less understood.
Although historians have acknowledged that pirates’ impact on slave trading capital prompted their “extermination” in the early eighteenth century, these assertions make it appear that influential merchants lobbied and the government responded with naval support. As has been discussed in the preceding chapters, government responses to mercantile petitions were much more complex than this. With multiple groups vying for the same finite naval resources, the government had to make decisions about where and when the Royal Navy was present in extra-European waters. Before 1719, naval vessels were not assigned to protect British trade in West Africa during peacetime and this only changed as pirates attacked British slaving vessels along the coast. The subsequent lobbying by competing groups of London-based slavers offers a revealing perspective into the mechanisms surrounding mercantile petitioning and its influence on the nature of British naval power in extra-European waters.
In 1726, an anonymous pamphlet published in London lamented the impact of Spanish maritime predation on Jamaican trade following the cessation of arms between Britain and Spain in 1712, which preceded the close of the War of the Spanish Succession (1702–13) one year later. In this pamphlet, the writer – identified only as “a person who resided several years at Jamaica” – described the predatory activities of Spanish guardacostas (coastguards) who were commissioned to suppress contraband trade on Spanish coasts, but who were accused of indefensible and violent assaults on British shipping throughout the Caribbean, particularly along the sea routes leading to and from Jamaica. According to the author, it was the immediate post-war actions of the guardacosta that “occassion[e]d the Rise of the English Pyrates, and laid the Foundation of all the Mischiefs which have happened by their Means”. By this account, the surge of piracy that occurred after 1716 was attributed to the geopolitical disputes that arose between British and Spanish subjects in the peacetime Caribbean concerning freedom of navigation and contraband trade.
Although recognised by contemporaries, the impact of Anglo-Spanish disputes in the peacetime Caribbean has not received attention within current understandings of early eighteenth-century piracy. Instead, there are two existing explanations for this surge. The first focuses on the centrality of privateering commissions issued by Archibald Hamilton, governor of Jamaica from 1710 to 1716, following the shipwreck of a Spanish flotilla in July 1715. After receiving their commissions, two Jamaican privateers sailed directly to the site of the wrecks and raided a Spanish salvaging camp that had been established on the adjacent shore. According to contemporary accounts, this raid netted the privateers 120,000 pieces of eight, which they carried back to Jamaica in January 1716. This then created a treasure-hunting sensation, which encouraged further voyages of British colonial vessels to the wrecks. In May, Hamilton's governorship was annulled and Jamaican privateers, as well as non-commissioned treasure hunters from Jamaica and elsewhere, were recalled to their respective ports and prohibited from salvaging the Spanish wrecks. Rather than return to colonial ports and face the potential loss of their accumulated plunder, these displaced mariners instead gathered at the Bahamas and turned to piracy.
In October 1717, Governor Walter Hamilton of the Leeward Islands reported to the Board of Trade that pirates who had formerly been impacting Caribbean trade had “all gon[e] to north america, or to some other parts”. This report coincided with the peak of pirate activity in North America, when pirates voyaged from New Providence and the Caribbean to the North American coast. Arriving in the summer and autumn months of 1717 and 1718, pirates targeted capes near to colonial ports for a short period, intercepting vessels before moving northward to the next chokepoint. They then returned to the Caribbean at the end of autumn to avoid the winter storms, before returning in spring. Throughout 1717 and 1718, there were frequent complaints of pirates operating in the capes and inlets off South Carolina, North Carolina, Virginia, Pennsylvania, New York, Rhode Island and Massachusetts, with attacks reported as far as Cape Sables in Newfoundland. While the number of vessels plundered by pirates in North America was relatively small over the duration of these two years, the short-term concentration of piratical attacks within colonial capes had an intermittent yet significant impact on regional trade. This, in turn, encouraged a number of local initiatives intended to chase pirates from nearby waters.
The success of British anti-piracy expeditions in North America in 1718, particularly against Edward Thache in North Carolina and Stede Bonnet in South Carolina, has ensured their inclusion in most studies of Atlantic piracy. Yet, these discussions provide little consideration of the organisation, funding and motivations behind these voyages, and do not consider what they suggest about the state of maritime defence in early eighteenth-century British North America. Instead, these expeditions are viewed as a turning point in a unified imperial project to curtail piracy throughout the British Atlantic. This aligns to the wider historiography of the British Atlantic, in which colonial maritime defence – including that provided by the Royal Navy – has received little focus beyond wartime privateering or naval assaults. Unlike British Caribbean colonies, which had largely been absorbed into royal control, British colonies settled along the eastern coast of North America continued to be made up of an assortment of royal and private colonies.
In July 1716, Alexander Spotswood, lieutenant-governor of Virginia from 1710 to 1722, wrote to the Board of Trade that a “nest of pirates” endeavoured to “establish themselves at [New] Providence”, warning that these would prove “dangerous to British commerce, if not timely suppressed”. Two years earlier, Henry Pulleine, governor of Bermuda from 1713 to 1718, had warned of pirates operating from New Providence, but the imperial administration had yet to act on the news. Several similar reports by British governors were prompted by the rapid increase of New Providence-based pirates from 1716 onwards and their transition from attacking Spanish vessels in the waters surrounding the Bahamas to indiscriminate attacks on colonial shipping throughout the Caribbean and North America. Despite these reports, the imperial administration only began to gradually respond to pirates from 1717 onwards after England-based mercantile groups complained about the impact of piracy on British transatlantic shipping. Consequently, the immediate responses to piracy in the Caribbean Sea before 1717 relied on the fragmented efforts of naval captains and colonial governments acting against pirates operating in waters near to their respective posts. When such undertakings occurred, they proved extremely limited and produced little change throughout the Caribbean. Similarly, when the British government responded in 1717, the measures imposed were obstructed by the lack of resources available to enact them. The result was that between 1714 and 1718 piracy was left largely unchecked in the Caribbean. This enabled pirates to not only accumulate plunder but also recruit additional crewmembers, capture larger vessels and outfit them with superior firepower in order to facilitate voyages against richer prizes further afield.
The lack of success against pirates prior to 1718 offers the opportunity to explore the factors that dictated the strength of imperial maritime power in extra-European spaces. As has been discussed in previous studies of the eighteenth-century Royal Navy, naval vessels stationed in extra-European spaces during peacetime were primarily instructed to provide for the protection of trade by convoying merchant shipping; the vessels were too few and too scattered to achieve anything beyond this. However, the operational difficulties that naval captains faced when they arrived in the Americas, due to obstructive legislation and environmental conditions, inhibited their ability to carry out these instructions effectively.
In June 1723, Barrow Harris, commander-in-chief of the naval vessels stationed in Jamaica, reported to the Admiralty that “We have had little or no damage done for some time in these parts by Pirates, only by some Spaniards that call themselves Guarda Coasts.” Echoing Harris, historians have generally agreed that a decline in piracy had occurred not just in the waters surrounding Jamaica but throughout the Atlantic Ocean by 1726. This, they argue, was the result of either military–legal campaigns, declining markets for plunder, the increased availability of marine insurance, or the changing perceptions of piracy in the colonial theatre. These studies offer important perspectives on crucial factors that helped bring about a stark decline in piracy by 1726, but they also conflate or simplify the events occurring throughout the ten-year surge in piracy to emphasise the importance of one group over another – whether naval captains, lawyers, merchants, journalists, or insurers. In contrast, this book has charted the fragmented efforts to curtail piracy as Atlantic pirates spread from the Bahamas and Florida to the Greater Caribbean, North America, West Africa and the Indian Ocean, and has established that various groups reacted to the impact of piracy in these waters and played a role in the successes and failures of British anti-piracy campaigns. This process continued after 1722 when the remaining active Atlantic pirates concentrated their attacks in the locales of the Caribbean Sea and North American coastline where a high volume of shipping trafficked but where there was little naval or colonial maritime protection.
Although there was a drop in piratical activity in the Americas between 1719 and 1721, coinciding with a number of pirate crews voyaging to Africa, Brazil and the East Indies, there continued to be reports of piracy in the Caribbean and North America. Despite this sustained presence, pirates do not appear to have significantly obstructed regional trade during these years and there were no anti-piracy expeditions in the Caribbean or North America by either naval warships or private vessels outfitted by colonial governments. This changed in 1722 when significantly more piracies were reported in North America and the Caribbean. Compared to piratical activity between 1716 and 1721, the numbers of Atlantic pirates operating after 1722 had significantly diminished and attacks came to be concentrated in regions that received no or only intermittent protection by naval and colonial guardships.