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OBJECTIVE:Individual patients with the same condition may respond differently to similar treatments. Our aim is to summarise the reporting of person-level heterogeneity of treatment effects (HTE) in multiperson N-of-1 studies and to examine the evidence for person-level HTE through reanalysis. STUDY DESIGN:Systematic review and reanalysis of multiperson N-of-1 studies. DATA SOURCES:Medline, Cochrane Controlled Trials, EMBASE, Web of Science and review of references through August 2017 for N-of-1 studies published in English. STUDY SELECTION:N-of-1 studies of pharmacological interventions with at least two subjects. DATA SYNTHESIS:Citation screening and data extractions were performed in duplicate. We performed statistical reanalysis testing for person-level HTE on all studies presenting person-level data. RESULTS:We identified 62 multiperson N-of-1 studies with at least two subjects. Statistical tests examining HTE were described in only 13 (21%), of which only two (3%) tested person-level HTE. Only 25 studies (40%) provided person-level data sufficient to reanalyse person-level HTE. Reanalysis using a fixed effect linear model identified statistically significant person-level HTE in 8 of the 13 studies (62%) reporting person-level treatment effects and in 8 of the 14 studies (57%) reporting person-level outcomes. CONCLUSIONS:Our analysis suggests that person-level HTE is common and often substantial. Reviewed studies had incomplete information on person-level treatment effects and their variation. Improved assessment and reporting of person-level treatment effects in multiperson N-of-1 studies are needed.

In recent years, several case reports and outbreaks reported occurrence of non-tuberculous mycobacteria (NTM) infections within 6 months after receiving a tattoo in healthy individuals. NTM species (e.g., Chelonae, Fortuitum, Hemophillum, and Abscessus) are widespread in the environment and it is often suspected that contamination may occur through unsterile instrumentation or unsterile water used for diluting tattoo ink to dilute color. In reported cases, lesions were mainly restricted to a single color ‘gray’ part of the tattoo. Mycobacterium Chelonae was the most common cause of tattoo associated NTM infections. Less than 50% of the case reports tested tattoo ink for acid fast bacilli stains and cultures. Subjects required treatment with either clarithromycin alone or in combination with quinolones for 6 to 9 months. An increase in NTM skin infections in healthy individuals after tattooing indicates the need for sterile standards during tattooing and improved local and regional regulatory oversight.

The Patient-Centered Outcomes Research Institute (PCORI) is a nonprofit, nongovernmental organization established by the U.S. Congress to fund comparative clinical effectiveness research focusing on patient-centered outcomes through the engagement of stakeholders. Evaluation of emerging healthcare innovations is one of PCORI’s five National Priorities for Health. One such initiative is PCORI’s Emerging Technologies and Therapeutics Reports program, established to provide timely overviews of evidence on new drugs and other healthcare technologies. This article provides an overview of completed and ongoing Emerging Technologies and Therapeutics Reports including lessons learned to date. In addition to systematic searches, systematic selection of studies, and transparent reporting of the available evidence, informed by a select number of stakeholders (i.e., key informants), these reports focus on contextual factors shaping the diffusion of emerging technologies that are often not reported in the medical literature. This article also compares processes and methodologies of health technology assessments (HTAs) from a selected number of national and international publicly funded agencies with a goal toward potential future enhancement of PCORI’s Emerging Technologies and Therapeutics Reports program. HTAs vary considerably in terms of funding, types of assessments, the role of manufacturers, stakeholder engagement, timeline to complete from the start to the finish of a draft report publication, and communication of uncertainty for informed decision making. Future Emerging Technologies and Therapeutics Reports may focus on rapid reports to support a more expedient development of evidence. Future research could explore the role of contextual factors identified in these reports on targeted evidence generation. [ABSTRACT FROM AUTHOR]

We conducted a systematic review to evaluate the association between folate, vitamin B-6, vitamin B-12, and cognitive function in the elderly. Our search was conducted in Medline for English-language publications of human subjects from 1966 through November 2006; we supplemented these results with information from article reviews and domain experts. We included longitudinal cohort and case-control studies of B vitamins and analyses of cognitive tests or Alzheimer's disease. We evaluated the quality and heterogeneity of study outcomes and assessed 30 different cognitive function tests. Of 24 studies that met eligibility criteria, 16 were determined to be of fair quality. A majority of the studies reviewed 2 or more B vitamins. Considerable heterogeneity was found among B-vitamin-level thresholds, comparisons, and data analyses. Six of 10 folate studies reported a significant association between low baseline blood folate concentrations and subsequent poor test performance in the global cognitive domain, and 4 of 9 folate studies found associations between low blood folate concentrations and increased prevalence of Alzheimer's disease. Studies did not reveal an association of vitamin B-6 and vitamin B-12 blood concentrations with cognitive-test performance or Alzheimer's disease, nor was B-vitamin dietary intake associated with cognitive function. Higher plasma homocysteine concentrations were associated with poorer cognitive function. Although the majority of studies indicated that low blood folate concentrations predicted poorer cognitive function, data supporting this association were limited because of the heterogeneity in cognition-assessment methodology, and scarcity of good quality studies and standardized threshold levels for categorizing low B-vitamin status.