Integrated analysis of transcriptome and small RNAome reveals regulatory network of rapid and long-term response to heat stress in Rhododendron moulmainense.

MAIN CONCLUSION: The post-transcriptional gene regulatory pathway and small RNA pathway play important roles in regulating the rapid and long-term response of Rhododendron moulmainense to high-temperature stress. The Rhododendron plays an important role in maintaining ecological balance. However, it is difficult to domesticate for use in urban ecosystems due to their strict optimum growth temperature condition, and its evolution and adaptation are little known. Here, we combined transcriptome and small RNAome to reveal the rapid response and long-term adaptability regulation strategies in Rhododendron moulmainense under high-temperature stress. The post-transcriptional gene regulatory pathway plays important roles in stress response, in which the protein folding pathway is rapidly induced at 4 h after heat stress, and alternative splicing plays an important role in regulating gene expression at 7 days after heat stress. The chloroplasts oxidative damage is the main factor inhibiting photosynthesis efficiency. Through WGCNA analysis, we identified gene association patterns and potential key regulatory genes responsible for maintaining the ROS steady-state under heat stress. Finally, we found that the sRNA synthesis pathway is induced under heat stress. Combined with small RNAome, we found that more miRNAs are significantly changed under long-term heat stress. Furthermore, MYBs might play a central role in target gene interaction network of differentially expressed miRNAs in R. moulmainense under heat stress. MYBs are closely related to ABA, consistently, ABA synthesis and signaling pathways are significantly inhibited, and the change in stomatal aperture is not obvious under heat stress. Taken together, we gained valuable insights into the transplantation and long-term conservation domestication of Rhododendron, and provide genetic resources for genetic modification and molecular breeding to improve heat resistance in Rhododendron.

The Proton of Alcohols as Hydrogen Source in Diboron-Mediated Nickel-Catalyzed Asymmetric Transfer Hydrogenation of Cyclic N-Sulfonyl Imines.

The proton of alcohols as the sole hydrogen source in diboron-mediated nickel-catalyzed asymmetric transfer hydrogenation of cyclic N-sulfonyl imines has been developed, providing the chiral cyclic sulfamidates in excellent enantioselectivities. The mechanistic investigations suggested that the proton of alcohols could be activated by tetrahydroxydiboron to form active nickel hydride species.

Palladium-Catalyzed Asymmetric Hydrogenation of Unprotected 3-Substituted Indoles.

A palladium-catalyzed asymmetric hydrogenation of unprotected 3-substituted indoles was developed, providing a series of 3-substituted indolines in excellent yields with ≤94.4:5.6 er. The large sterically hindered bisphosphine ligand played a crucial role in the enantioselective control. In addition, the gram-scale hydrogenation experiment and product derivatizations were performed successfully.

The impact of hospital harm on length of stay, costs of care and length of person-centred episodes of care: a retrospective cohort study.

BACKGROUND: There is a lack of data in Canada on the longitudinal effects of adverse events that occur in hospital, specifically in the period after discharge. Our objective was to quantify the impact of adverse events on hospital length of stay, length of person-centred episodes of care (PCEs) and costs of PCEs, as well as their impact on the total health system. METHODS: We conducted a population-based, retrospective cohort study using linked health administrative databases. We included adults in Ontario who had an acute hospital admission between Apr. 1, 2015, and Mar. 31, 2016. We grouped hospital admissions into 1 of 9 episode types and used the Canadian Institute for Health Information methodology for hospital harm to measure adverse events. We specified generalized linear models to estimate the impact of hospital harm on the following: incremental length of index acute hospital admission, incremental length of the PCE, and incremental costs of the PCE. RESULTS: Out of 610 979 hospital admissions, 36 004 (5.9%) involved an occurrence of harm. The impact of harm on the incremental length of hospital stay ranged from 0.4 to 24.2 days (p < 0.001); the incremental length of the PCE ranged from 0.3 to 30.2 days (p < 0.001); and the incremental costs of the PCE ranged from $800 to $51 067 (p < 0.001). Total hospital days attributable to hospital harm amounted to 407 696, and the total attributable cost to the Ontario health system amounted to $1 088 330 376. INTERPRETATION: We found that experiencing harm in hospital significantly affects both in-hospital and post-discharge use of health services and costs of care, and constitutes an enormous expense to Ontario's publicly funded health system.

Patterns of healthcare utilisation for respiratory complications of adults with neuromuscular disease: a population study.

Our objective was to quantify health service utilisation including monitoring and treatment of respiratory complications for adults with neuromuscular disease (NMD), identifying practice variation and adherence to guideline recommendations at a population level.We conducted a population-based longitudinal cohort study (2003-2015) of adults with NMD using hospital diagnostic and health insurance billing codes within administrative health databases.We identified 185 586 adults with NMD. Mean age 52 years, 59% female. 41 173 (22%) went to an emergency department for respiratory complications on average 1.6 times every 3 years; 14 947 (8%) individuals were admitted to hospital 1.4 times every 3 years. Outpatient respiratory specialist visits occurred for 64 084 (35%) with four visits every 3 years, although substantial variation in visit frequency was found. 157 285 (85%) went to the emergency department (all-cause) almost 4 times every 3 years, 100 052 (54%) were admitted to hospital. Individuals with amyotrophic lateral sclerosis/motor neurone disease (ALS/MND) had more emergency department visits compared with other types of NMD (p<0.0001).One-third of adults with NMD received respiratory specialist care at a frequency recommended by professional guidelines, although substantial variation exists. Emergent healthcare utilisation was substantial, emphasising the burden of NMD on the healthcare system and urgent need to improve community and social supports, particularly for ALS/MND patients.

Assessing the representativeness of physician and patient respondents to a primary care survey using administrative data.

BACKGROUND: QUALICOPC is an international survey of primary care performance. QUALICOPC data have been used in several studies, yet the representativeness of the Canadian QUALICOPC survey is unknown, potentially limiting the generalizability of findings. This study examined the representativeness of QUALICOPC physician and patient respondents in Ontario using health administrative data. METHODS: This representativeness study linked QUALICOPC physician and patient respondents in Ontario to health administrative databases at the Institute for Clinical Evaluative Sciences. Physician respondents were compared to other physicians in their practice group and all Ontario primary care physicians on demographic and practice characteristics. Patient respondents were compared to other patients rostered to their primary care physicians, patients rostered to their physicians' practice groups, and a random sample of Ontario residents on sociodemographic characteristics, morbidity, and health care utilization. Standardized differences were calculated to compare the distribution of characteristics across cohorts. RESULTS: QUALICOPC physician respondents included a higher proportion of younger, female physicians and Canadian medical graduates compared to other Ontario primary care physicians. A higher proportion of physician respondents practiced in Family Health Team models, compared to the provincial proportion for primary care physicians. QUALICOPC patient respondents were more likely to be older and female, with significantly higher levels of morbidity and health care utilization, compared with the other patient groups examined. However, when looking at the QUALICOPC physicians' whole rosters, rather than just the patient survey respondents, the practice profiles were similar to those of the other physicians in their practice groups and Ontario patients in general. CONCLUSIONS: Comparisons revealed some differences in responding physicians' demographic and practice characteristics, as well as differences in responding patients' characteristics compared to the other patient groups tested, which may have resulted from the visit-based sampling strategy. Ontario QUALICOPC physicians had similar practice profiles as compared to non-participating physicians, providing some evidence that the participating practices are representative of other non-participating practices, and patients selected by visit-based sampling may also be representative of visiting patients in other practices. Those using QUALICOPC data should understand this limited representativeness when generalizing results, and consider the potential for bias in their analyses.

Direct medical costs of motorcycle crashes in Ontario.

BACKGROUND: There is no reliable estimate of costs incurred by motorcycle crashes. Our objective was to calculate the direct costs of all publicly funded medical care provided to individuals after motorcycle crashes compared with automobile crashes. METHODS: We conducted a population-based, matched cohort study of adults in Ontario who presented to hospital because of a motorcycle or automobile crash from 2007 through 2013. For each case, we identified 1 control absent a motor vehicle crash during the study period. Direct costs for each case and control were estimated in 2013 Canadian dollars from the payer perspective using methodology that links health care use to individuals over time. We calculated costs attributable to motorcycle and automobile crashes within 2 years using a difference-in-differences approach. RESULTS: We identified 26 831 patients injured in motorcycle crashes and 281 826 injured in automobile crashes. Mean costs attributable to motorcycle and automobile crashes were $5825 and $2995, respectively (p < 0.001). The rate of injury was triple for motorcycle crashes compared with automobile crashes (2194 injured annually/100 000 registered motorcycles v. 718 injured annually/100 000 registered automobiles; incidence rate ratio [IRR] 3.1, 95% confidence interval [CI] 2.8 to 3.3, p < 0.001). Severe injuries, defined as those with an Abbreviated Injury Scale ≥ 3, were 10 times greater (125 severe injuries annually/100 000 registered motorcycles v. 12 severe injuries annually/100 000 registered automobiles; IRR 10.4, 95% CI 8.3 to 13.1, p < 0.001). INTERPRETATION: Considering both the attributable cost and higher rate of injury, we found that each registered motorcycle in Ontario costs the public health care system 6 times the amount of each registered automobile. Medical costs may provide an additional incentive to improve motorcycle safety.

Palliative care delivery across health sectors: A population-level observational study.

BACKGROUND: Little population-level information exists about the delivery of palliative care across multiple health sectors, important in providing a complete picture of current care and gaps in care. AIM: Provide a population perspective on end-of-life palliative care delivery across health sectors. DESIGN: Retrospective population-level cohort study, describing palliative care in the last year of life using linked health administrative databases. SETTING/PARTICIPANTS: All decedents in Ontario, Canada, from 1 April 2010 to 31 March 2012 ( n = 177,817). RESULTS: Across all health sectors, about half (51.9%) of all decedents received at least one record of palliative care in the last year of life. Being female, middle-aged, living in wealthier and urban neighborhoods, having cancer, and less multi-morbidity were all associated with higher odds of palliative care receipt. Among 92,276 decedents receiving palliative care, 84.9% received care in acute care hospitals. Among recipients, 35 mean days of palliative care were delivered. About half (49.1%) of all palliative care days were delivered in the last 2 months of life, and half (50.1%) had palliative care initiated in this period. Only about one-fifth of all decedents (19.3%) received end-of-life care through publicly funded home care. Less than 10% of decedents had a record of a palliative care home visit from a physician. CONCLUSION: We describe methods to capture palliative care using administrative data. Despite an estimate of overall reach (51.9%) that is higher than previous estimates, we have shown that palliative care is infrequently delivered particularly in community settings and to non-cancer patients and occurs close to death.

The association between multimorbidity and hospitalization is modified by individual demographics and physician continuity of care: a retrospective cohort study.

BACKGROUND: Multimorbidity poses a significant clinical challenge and has been linked to greater health services use, including hospitalization; however, we have little knowledge about the influence of contextual factors on outcomes in this population. OBJECTIVES: To describe the extent to which the association between multimorbidity and hospitalization is modified by age, gender, primary care practice model, or continuity of care (COC) among adults with at least one chronic condition. METHODS: A retrospective cohort study with linked population-based administrative data. SETTING: Ontario, Canada. COHORT: All individuals 18 and older with at least one of 16 priority chronic conditions as of April 1, 2009 (baseline). MAIN OUTCOME MEASURES: Any hospitalization, 3 or more hospitalizations, non-medical discharge delay, and 30-day readmission within the 1 year following baseline. RESULTS: Of 5,958,514 individuals, 484,872 (8.1 %) experienced 646,347 hospitalizations. There was a monotonic increase in the likelihood of hospitalization and related outcomes with increasing multimorbidity which was modified by age, gender, and COC but not primary care practice model. The effect of increasing multimorbidity was greater in younger adults than older adults and in those with lower COC than with higher COC. The effect of increasing multimorbidity on hospitalization was greater in men than women but reversed for the other outcomes. CONCLUSIONS: The effect of multimorbidity on hospitalization is influenced by age and gender, important considerations in the development of person-centred care models. Greater continuity of physician care lessened the effect of multimorbidity on hospitalization, further demonstrating the need for care continuity across providers for people with chronic conditions.

Evaluating the late career nurse initiative: a cross-sectional survey of senior nurses in Ontario.

AIM: This study evaluated the impact of the late career nurse initiative on nurse perceptions of their work environment, workplace burnout, job satisfaction, organisational commitment and intention to remain. BACKGROUND: The Ontario Ministry of Health and Long-Term Care introduced the late career nurse initiative with the goal of improving the retention of front-line nurses aged 55 and over by implementing a 0.20 full-time equivalent reduction of physically or psychologically demanding duties, enabling nurses to engage in special projects for the improvement of their organisations and patient care. METHODS: A sample of 902 nurses aged 55 and over from acute and long-term care facilities were surveyed using valid and reliable questionnaires. RESULTS: Nurses who had participated in the initiative did not differ significantly from those who had not in terms of workplace burnout, job satisfaction, length of service or intention to remain within their current organisation. The late career nurse initiative participants reported significantly higher perceptions of managers' ability, leadership and support and their level of participation in hospital affairs. CONCLUSION: The late career nurse initiative was associated with perceived differences in nurses' work environment but not outcomes. IMPLICATIONS FOR NURSING MANAGEMENT: Leaders need to pay attention to how late career nurses are selected and matched to organisational projects.

The relationship among evidence-based practice and client dyspnea, pain, falls, and pressure ulcer outcomes in the community setting.

BACKGROUND: There are gaps in knowledge about the extent to which home care nurses' practice is based on best evidence and whether evidence-based practice impacts patient outcomes. AIM: The purpose of this study was to investigate the relationship between evidence-based practice and client pain, dyspnea, falls, and pressure ulcer outcomes in the home care setting. Evidence-based practice was defined as nursing interventions based on best practice guidelines. METHODS: The Nursing Role Effectiveness model was used to guide the selection of variables for investigation. Data were collected from administrative records on percent of visits made by Registered Nurses (RN), total number of nursing visits, and consistency of visits by principal nurse. Charts audits were used to collect data on nursing interventions and client outcomes. The sample consisted of 338 nurses from 13 home care offices and 939 de-identified client charts. Hierarchical generalized linear regression approaches were constructed to explore which variables explain variation in client outcomes. RESULTS: The study found documentation of nursing interventions based on best practice guidelines was positively associated with improvement in dyspnea, pain, falls, and pressure ulcer outcomes. Percent of visits made by an RN and consistency of visits by a principal nurse were not found to be associated with improved client outcomes, but the total number of nursing visits was. LINKING EVIDENCE TO ACTION: Implementation of best practice is associated with improved client outcomes in the home care setting. Future research needs to explore ways to more effectively foster the documentation of evidence-based practice interventions.

Manganese Pentacarbonyl Bromide as Regeneration Catalyst Enabled Biomimetic Asymmetric Reduction.

Using readily available manganese pentacarbonyl bromide as a regeneration catalyst, biomimetic asymmetric reduction of imines including quinoxalinones, benzoxazinones, and benzoxazine has been successfully developed in the presence of transfer catalyst chiral phosphoric acids, providing the chiral amines with high yields and enantioselectivities.

Pestalotiopsis jiangsuensis sp. nov. Causing Needle Blight on Pinus massoniana in China.

Pinus massoniana Lamb. is an important, common afforestation and timber tree species in China. Species of Pestalotiopsis are well-known pathogens of needle blight. In this study, the five representative strains were isolated from needle blight from needles of Pi. massoniana in Nanjing, Jiangsu, China. Based on multi-locus phylogenetic analyses of the three genomic loci (ITS, TEF1, and TUB2), in conjunction with morphological characteristics, a new species, namely Pestalotiopsis jiangsuensis sp. nov., was described and reported. Pathogenicity tests revealed that the five representative strains of the species described above were pathogenic to Pi. massoniana. The study revealed the diversity of pathogenic species of needle blight on Pi. massoniana. This is the first report of needle blight caused by P. jiangsuensis on Pi. massoniana in China and worldwide. This provides useful information for future research on management strategies of this disease.

Healthcare Utilization and Costs in Children Receiving Home Mechanical Ventilation in Ontario: A 14-Year Cohort Study.

RATIONALE: Home mechanical ventilation (HMV) is an advanced medical therapy offered to children with medical complexity. Despite the growing pediatric HMV population in North America, there are limited studies describing healthcare utilization and predictors of highest costs using robust health administrative data. OBJECTIVES: To describe patterns of healthcare utilization and costs in children receiving HMV over a 14-year period in Ontario, Canada. METHODS: We conducted a retrospective population-based cohort study (April 1, 2003 to March 31, 2017) of children aged 0-18 years receiving HMV via invasive mechanical ventilation (IMV) or non-invasive ventilation (NIV). Paired t-tests compared healthcare system utilization and costs two years before and two years after HMV approval. We developed linear models to analyze variables associated with children in the top quartile of health service utilization and costs. RESULTS: We identified 835 children receiving HMV. In the two years after HMV approval compared to the 2 years prior, children had decreased hospitalization days (median 9 (IQR 3-30) versus 29 (6-99), p<0.0001) and ICU admission days (6.6 (1.9-18.0) versus 17.1 (3.3-70.9), p<0.0001) but had increased homecare service approvals (195 (24-522) versus 40 (12-225), p<0.0001) and outpatient Pulmonology visits (3 (1-4) versus 2 (1-3), p<0.0001). Total healthcare costs were higher in the two years after HMV approval (mean $164,892 (SD $214,187) versus $128,941 ($194,199), p<0.0001). However, all-cause hospital admission costs were reduced ($66,546 ($142,401) versus $81,578 ($164,672), p<0.0001). Highest total 2-year costs were associated with IMV (OR 3.45, 95% CI 2.24-5.31; reference NIV), number of medical devices at home (OR 1.63, 95% CI 1.35-1.96; reference no technology), and increased healthcare costs in the year prior to HMV initiation (OR 2.23, 95% CI 1.84-2.69). CONCLUSIONS: Children progressing to the need for HMV represent a worsening in their respiratory status that will undoubtedly increase healthcare utilization and costs. We found that the initiation of HMV in these children can reduce inpatient healthcare utilization and costs but can still increase overall healthcare expenditures, especially in the outpatient setting.

A formative evaluation of nurses' use of electronic devices in a home care setting.

The purpose of this study was to evaluate the implementation of a clinical information system (CIS) in a community setting. The researchers used a mixed-method design involving interviews, focus groups, and surveys. An independent cross-sectional sample of nurses was surveyed. At time 1 a total of 118 nurses responded and at time 2 a total of 81. Respondents were moderately satisfied with features of the CIS. User satisfaction was positively associated with access to structural and electronic resources and social capital and negatively associated with nurses' age at time 1. Social capital was positively associated with user satisfaction at time 2. Younger age was associated with overall research use at both time 1 and time 2. Research use was negatively associated with evaluation and feedback but positively associated with formal interactions. This evaluation identified the importance of educational support, user-centred design, and responsiveness to successful implementation of CISs in a community setting.

An interrupted time series study using administrative health data to examine the impact of the COVID-19 pandemic on alternate care level acute hospitalizations in Ontario, Canada.

BACKGROUND: Many health systems struggle with delayed discharges (known as alternate level of care [ALC] in Canada). Our objectives were to describe and compare patient and hospitalization characteristics by ALC status, and to examine the impact of the initial period of the COVID-19 pandemic on ALC rates in Ontario, Canada. METHODS: We conducted an interrupted time series using linked administrative data for acute care hospital discharges in Ontario between Feb. 28, 2018, and Nov. 30, 2020. We measured the monthly ALC rate among discharges before and after the onset of the COVID-19 pandemic (Mar. 1, 2020). We used interrupted time series regressions to examine the association between the onset of the pandemic and average ALC monthly rates. RESULTS: We identified no meaningful differences in patient and admission characteristics, irrespective of time; however, differences were identified by ALC status. The overall average monthly rate of ALC discharges before the COVID-19 pandemic was 4.9% and after the onset of the pandemic was 5.0%. These discharges dropped to 4.3% (n = 3558) in March 2020 but then rebounded to their peak of 5.8% (n = 3915). There was no significant change in the average level of ALC rates per month after the onset of the pandemic (increase of 0.36% average per month, 95% confidence interval [CI] -0.11% to 0.83%) or monthly rate of change (slope) after the onset of the pandemic (-0.08%, 95% CI -0.15 to 0). INTERPRETATION: We identified a continued high rate of hospital discharges with an ALC component despite the considerable efforts in hospital to reduce hospital occupancy during the COVID-19 pandemic. Future research should examine why ALC rates remain high despite hospital efforts.

Palladium-catalyzed asymmetric allenylic alkylation: construction of multiple chiral thiochromanone derivatives.

The development of a new strategy for the construction of chiral cyclic sulfide-containing multiple stereogenic centers is highly desirable. Herein, by the combination of base-promoted retro-sulfa-Michael addition and palladium-catalyzed asymmetric allenylic alkylation, the streamlined synthesis of chiral thiochromanones containing two central chiralities (including a quaternary stereogenic center) and an axial chirality (allene unit) was successfully realized with up to 98% yield, 49.0 : 1 dr and >99% ee.

Non-adherence to COPD medications and its association with adverse events: A longitudinal population based cohort study of older adults.

OBJECTIVE: To determine the association between non-adherence to long term chronic obstructive pulmonary disease (COPD) medications and COPD related emergency department (ED) visits and hospitalizations in patients with incident COPD, utilizing time varying measures of adherence as well as accounting for time-varying confounding impacted by prior adherence. STUDY DESIGN AND SETTING: We conducted a population-based retrospective cohort study between 2007-2017 among individuals aged 66 years and older with incident COPD using multiple linked administrative health databases from the province of Ontario, Canada. Adherence to COPD medications was measured using time varying proportion of days covered based on insurance claims for medications dispensed at community pharmacies. The parametric g-formula was used to assess the association between time-varying adherence (in the last 90-days) to COPD medications and risk of COPD related hospitalizations and ED visits while accounting for time varying confounding by COPD severity. RESULTS: Overall, 60,251 individuals with incident COPD were included; mean age was 76 (SD 7) and 59% were male. Mean adherence over the entire follow-up was 23% (SD 0.3). There were 7248 (12%) COPD related ED visits (2.8 events per 100 person years [PY]) and 9188 (15%) COPD related hospitalizations (3.5 events per 100 PY). Compared to those with 0% 90-day adherence, those with adherence between 1-33% had a 19% decreased risk of COPD related ED visits (adjusted risk ratio[aRR]:0.81, 95% confidence interval [CI]:0.78-0.83), those with adherence between 34%-67% had a 18% decreased risk (aRR: 0.82, 95% CI: 0.77-0.85) while those with 68%-100% 90-day adherence had a 63% increased risk of COPD related ED visits (aRR: 1.63, 95% CI: 1.47-1.78). Nearly identical results were obtained for COPD specific hospitalizations. CONCLUSION: After accounting for time varying confounding by COPD severity, the highest time varying 90-days adherence was associated with an increased risk of both COPD related ED visits and hospitalizations compared to the lowest adherence categories. Differences in COPD severity between adherence categories, perception of need for medication management in the higher adherence categories, and potential residual confounding makes it difficult to disentangle the independent effects of adherence from the severity of the condition itself.

Incidence and Mortality of Children Receiving Home Mechanical Ventilation.

OBJECTIVES: The incidence, as well as the predictors of mortality, for children receiving home mechanical ventilation (HMV) using population-based data in Canada is a current knowledge gap. Our objectives were to describe HMV incidence and mortality rates, and associations of demographic and clinical variables on mortality. METHODS: Using Ontario health and demographic administrative databases, we conducted a retrospective cohort study (April 1, 2003-March 31, 2017) of children aged 0 to 17 years receiving HMV via invasive mechanical ventilation and noninvasive ventilation. We identified children with complex chronic conditions. We used data from Census Canada to calculate incidence rates and Cox proportional hazards modeling to assess for predictors of mortality. RESULTS: We identified 906 children with a mean (SD) crude incidence rate of 2.4 (0.6) per 100 000 for pediatric HMV approvals that increased by 37% over the 14-year study period. Compared with children who were invasively ventilated, we found mortality was associated with noninvasive ventilation (adjusted hazard ratio [aHR], 1.9; 95% confidence interval [CI], 1.3-2.8). Mortality was highest in children from families in the lowest income quintile (aHR, 2.5; 95% CI, 1.5-4.0), those with neurologic impairment complex chronic conditions (aHR, 2.9; 95% CI, 1.4-6.4), those aged 11 to 17 years at HMV initiation (aHR, 1.5; 95% CI, 1.1-2.0), and those with higher health care costs in the 1 year before HMV initiation (aHR, 1.5; 95% CI, 1.3-1.7). CONCLUSIONS: The incidence of children receiving HMV increased substantially over the 14-year period. Demographic variables associated with increased mortality were identified, suggesting areas requiring greater attention for care providers.

How do respondents of primary care surveys compare to typical users of primary care? A comparison of two surveys.

BACKGROUND: Primary care surveys are a key source of evaluative data; understanding how survey respondents compare to the intended population is important to understand results in context. The objective of this study was to examine the physician and patient representativeness of two primary care surveys (TRANSFORMATION and QUALICOPC) that each used different sampling and recruitment techniques. METHODS: We linked the physician and patient participants of the two surveys to health administrative databases. Patients were compared to other patients visiting the practice on the same day and other randomly selected dates using sociodemographic data, chronic disease diagnosis, and health system utilization. Physicians were compared to other physicians in the same practice, and other physicians in the intended geographic area using sociodemographic and practice characteristics. RESULTS: Physician respondents of the TRANSFORMATION survey included more males compared to their practice groups, but not to other physicians in the area. TRANSFORMATION physicians cared for a larger roster of patients than other physicians in the area. Patient respondents of the QUALICOPC survey did not have meaningful differences from other patients who visit the practice. Patient respondents of the TRANSFORMATION survey resided in more rural areas, had less chronic disease, and had lower use of health services than other patients visiting the practice. CONCLUSION: Differences in survey recruitment methods at the physician and patient level may help to explain some of the differences in representativeness. When conducting primary care surveys, investigators should consider diverse methods of ensuring representativeness to limit the potential for nonresponse bias.