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Problem
Theoretical sampling is a key research process within grounded theory. However, whilst methodological texts provide a definition, it is difficult to find examples of how theoretical sampling is undertaken as a study develops. The lack of clear exemplars has caused confusion amongst researchers, with many grounded theory studies providing no evidence of theoretical sampling.Aim
This paper aims to demonstrate the theoretical sampling process as a grounded theory study progresses.Methods
A constructivist grounded theory study of bereaved parents’ experiences when their child dies in intensive care is used to illustrate the processes of theoretical sampling. Twenty-six bereaved parents participated in semi-structured, audio-recorded interviews. Data were analysed using constant comparative methods and theoretical memoing, with a theory developed that explained the changing nature of the parent-healthcare provider relationship when a child dies in intensive care.Findings
In this study, theoretical sampling necessitated the use of three different data collection techniques: Seeking new data collection sites, adding new interview questions, and sampling for specific participant characteristics. Each technique is discussed in detail and linked to the category and theory development in the exemplar study.Discussion
Though there are limitations to describing theoretical sampling processes on paper, clearly documented accounts can help novice researchers become familiar with the techniques involved and appreciate the benefits they bring to overall theory development.Conclusion
By providing a clear example of theoretical sampling linked to category and theory development, this paper has demonstrated the real world application of theoretical sampling in practice. 相似文献Methods: We described how NPDS data informed three public health responses: the Deepwater Horizon incident, national exposures to laundry detergent pods, and national exposures to e-cigarettes. Additionally, we extracted survey results of state epidemiologists regarding NPDS incident notification follow-up from 1 January 2015 to 31 December 2016 to assess current public health application of NPDS data using Epi Info 7.2 and analyzed data using SAS 9.3. We assessed whether state health departments were aware of incidents before notification, what actions were taken, and whether CDC notifications contributed to actions.
Discussion: NPDS data provided evidence for industry changes to improve laundry detergent pod containers safety and highlighted the need to regulate e-cigarette sale and manufacturing. NPDS data were used to improve situational awareness during the 2010 Deepwater Horizon oil spill. Of 59 health departments and PCs who responded to CDC notifications about anomalies (response rate = 49.2%), 27 (46%) reported no previous awareness of the incident, and 20 (34%) said that notifications contributed to public health action.
Conclusions: Monitoring NPDS data for anomalies can identify emerging public health threats and provide evidence-based science to support public health action and policy changes. 相似文献
Objective
To determine whether kidney function level and its rate of decline in the immediate predialysis period among veterans transitioning to end-stage renal disease (ESRD) predict postdialysis mortality and hospitalization.Patients and Methods
In 19,985 veterans transitioning to ESRD during the period October 1, 2007, to March 30, 2014, we examined kidney function and its slope over the final year of the pre-ESRD(prelude) period. Two categories of low vs high estimated glomerular filtration rate (eGFR, dichotomized at 10 mL/min/1.73 m2) and slow vs fast slope (dichotomized at ?10 mL/min/1.73 m2/y) were combined into 4 groups. Their associations with 12-month post-ESRD all-cause and cardiovascular (CV) mortality and hospitalization rates were examined in adjusted models accounting for clinical characteristics and laboratory measurements at transition.Results
Patients, 66±11 years old, and 34% blacks, had a median (interquartile range) eGFR at transition and slope of 9.7 (7.1-13.3) mL/min/1.73 m2 and ?10.5 (?18.8 to ?5.9) mL/min/1.73 m2/y, respectively. Patients with a low eGFR and slow slope had the lowest 12-month all-cause and CV mortality risks and hospitalization rate. Conversely, patients with high eGFR and fast slope had the highest risk of all-cause and CV mortality and hospitalization rate compared with patients with a low eGFR and slow slope. This relationship persisted in sensitivity analyses, including propensity scoring.Conclusion
A kidney profile of a low eGFR and slow slope in the prelude period is associated with favorable early dialysis outcomes in veteran patients. Trials to examine a more conservative approach to dialysis are warranted. 相似文献Ceriello and colleagues recently proposed a model of care that incorporates the collaborative use of structured SMBG into a formal approach to personalized diabetes management within all diabetes populations. We adapted this model for use in CSII-treated patients in order to enable the implementation of a workflow structure that enhances patient–physician communication and supports patients’ diabetes self-management skills.
We recognize that time constraints and current reimbursement policies pose significant challenges to healthcare providers integrating the Personalised Diabetes Management (PDM) process into clinical practice. We believe, however, that the time invested in modifying practice workflow and learning to apply the various steps of the PDM process will be offset by improved workflow and more effective patient consultations. This article describes how to implement PDM into clinical practice as a systematic, standardized process that can optimize CSII therapy. 相似文献