Even in a well-designed and controlled study, missing data occurs in almost all research. Missing data can reduce the statistical power of a study and can produce biased estimates, leading to invalid conclusions. This manuscript reviews the problems and types of missing data, along with the techniques for handling missing data. The mechanisms by which missing data occurs are illustrated, and the methods for handling the missing data are discussed. The paper concludes with recommendations for the handling of missing data.
Bias (Epidemiology) ; Handling (Psychology)

BACKGROUND: To date, various types of acellular dermal matrix (ADM) have been developed for clinical use. AlloDerm is the most familiar type of ADM to most surgeons in breast reconstruction. It is prepared by freeze-drying. CG CryoDerm is the first form of ADM that requires no drying process. Therefore, theoretically, it has a higher degree of preservation of the dermal structures than AlloDerm. We conducted this study to compare the clinical course and postoperative outcomes of patients who underwent direct-to-implant breast reconstructions using AlloDerm and those who did using CG CryoDerm. METHODS: We performed a retrospective analysis of the medical records in a consecutive series of 50 patients who underwent direct-to-implant breast reconstruction using AlloDerm (n=31) or CryoDerm (n=19). We then compared the clinical course and postoperative outcomes of the two groups based on the overall incidence of complications and the duration of drainage. RESULTS: The mean follow-up period was 16 months. There were no significant differences in the overall incidence of complications (seroma, infection, skin flap necrosis, capsular contracture, and implant loss) between the two groups. Nor was there any significant difference in the duration of drainage. CONCLUSIONS: CG CryoDerm has the merits of short preparation time and easy handling during surgery. Our results indicate that CG CryoDerm might be an alternative allograft material to AlloDerm in direct-to-implant breast reconstruction.
Acellular Dermis ; Breast ; Breast Implantation ; Collagen ; Contracture ; Female ; Follow-Up Studies ; Handling (Psychology) ; Humans ; Incidence ; Mammaplasty ; Medical Records ; Necrosis ; Retrospective Studies ; Skin ; Transplantation, Homologous

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is becoming a standard method for invasive mediastinal staging and for the diagnosis of paratracheal and peribronchial lesions. It is essential to understand the technical aspects of EBUS-TBNA to ensure safe and efficient procedures. In this review, we discuss the practical aspects to be considered during EBUS-TBNA, including anesthesia, manipulation of equipment, understanding mediastinal ultrasound images, target selection, number of aspirations needed per target, sample handling, and complications.
Anesthesia ; Aspirations (Psychology) ; Bronchoscopy ; Handling (Psychology) ; Lung Neoplasms ; Needles* ; Ultrasonography

Quite high prevalence of acute and chronic complications of calcaneal fractures has been reported. Acute complications include blisters, wound necrosis or infection. Late complications include subtalar arthritis, calcaneal malunion, lateral subfibular impingement, tendon problems, sural nerve complications. There are many surgical or nonsurgical treatment modalities to manage those complications. However strategic initial surgical approach with gentle soft tissue handling accompanied by comprehensive understanding about numerous complications might be the best tool to achieve pain free and functional heel after treating calcaneal fractures.
Arthritis ; Blister ; Calcaneus ; Handling (Psychology) ; Heel ; Necrosis ; Organic Chemicals ; Prevalence ; Sural Nerve ; Tendons

Hypertension is closely related to salt and water retention. The kidney plays an important role in the blood pressure regulation primarily to modulating tubular sodium and water reabsorption. The regulation of the salt and water balance depends upon an array of solute and water channels in the renal tubules. An altered regulation of sodium and water channels in the kidney may be related to various pathological conditions associated with altered salt and water retention. This review will discuss renal handling of sodium and water, with particular emphasis on aquaporins and renal sodium transporters and channels.
Aquaporins ; Blood Pressure ; Handling (Psychology) ; Hypertension ; Kidney ; Membrane Transport Proteins ; Retention (Psychology) ; Sodium ; Water

This study describes the characteristics of injuries and high risk situation in the Korean professional soccer matches using the video analysis. Video analysis is a video based method describing incidents and injuries that may result in an injury using 19 variables and categories modified from the soccer matches. During the 2012 season K-league, video files from 60 matches in the Korean professional soccer matches were reviewed. Injuries and Incidents were recorded when the match was interrupted by the referee because of a suspected injury. As results, 201 incidents were recorded in 60 matches. The most injured body part was ankle. The majority of the injury risk incidents occurred during receiving the ball and heading. Midfielders appeared to be at greater risk than others and most incidents and injuries occurred during breakdown attacks and when a player was involved in duels. Also, improved ball handling skill (especially 1st touching the ball) may reduce the incidents and injuries.
Animals ; Ankle ; Athletic Injuries ; Football ; Handling (Psychology) ; Head ; Seasons ; Soccer ; Sports

PURPOSE: Recently many cases of appendectomy have been conducted by single-incision laparoscopic technique. The aim of this study is to figure out the benefits of transumbilical single-port laparoscopic appendectomy (TULA) compared with conventional three-port laparoscopic appendectomy (CTLA). METHODS: From 2010 to 2012, 89 patients who were diagnosed as acute appendicitis and then underwent laparoscopic appendectomy a single surgeon were enrolled in this study and with their medical records were reviewed retrospectively. Cases of complicated appendicitis confirmed on imaging tools and patients over 3 points on the American Society of Anesthesia score were excluded. RESULTS: Among the total of 89 patients, there were 51 patients in the TULA group and 38 patients in the CTLA group. The visual analogue scale (VAS) of postoperative day (POD) #1 was higher in the TULA group than in the CTLA group (P = 0.048). The operative time and other variables had no statistical significances (P > 0.05). CONCLUSION: Despite the insufficiency of instruments and the difficulty of handling, TULA was not worse in operative time, VAS after POD #2, and the total operative cost than CTLA. And, if there are no disadvantages of TULA, TULA may be suitable in substituting three-port laparoscopic surgery and could be considered as one field of natural orifice transluminal endoscopic surgery with the improvement and development of the instruments and revised studies.
Anesthesia ; Appendectomy ; Appendicitis ; Handling (Psychology) ; Hospital Costs ; Humans ; Laparoscopy ; Medical Records ; Natural Orifice Endoscopic Surgery ; Operative Time ; Retrospective Studies

Duplicated ureters are the most common congenital malformation of the upper urinary tract, but there are few reports on the transplantation of kidneys with duplicated ureters. We introduce different techniques for the ureteroneocystostomy of double ureters and long-term results. We specifically detail the experience of two patients with duplicated ureters at Bong Seng Memorial Hospital from March 1995 to May 2012. In our first case, the top technique of spatulating and suturing duplicated ureters was applied with the bottom technique for double ureteroneocystostomy. The operation time was 4 hours and 45 minutes, while the ureteroneocystostomy took 32 minutes. In the second case a double-armed 4.0 Vicryl suture was placed on each tip of the ureter and both needles passed from the inside out through the bladder wall. The ureters were pulled into the bladder and the suture was tied on the serosa of the bladder. The operation time was 3 hours and 50 minutes, while the ureteroneocystostomy took 15 minutes. Neither urological complications nor urinary tract infections were observed in the follow-up period and no double-J stent was needed. We therefore conclude that these two techniques are available procedures for handling duplicated ureters, with the technique applied in the second case particularly time-effective.
Follow-Up Studies ; Handling (Psychology) ; Humans ; Kidney ; Kidney Transplantation ; Needles ; Polyglactin 910 ; Serous Membrane ; Stents ; Sutures ; Transplants ; Ureter ; Urinary Bladder ; Urinary Tract ; Urinary Tract Infections

Metagenomics has become one of the indispensable tools in microbial ecology for the last few decades, and a new revolution in metagenomic studies is now about to begin, with the help of recent advances of sequencing techniques. The massive data production and substantial cost reduction in next-generation sequencing have led to the rapid growth of metagenomic research both quantitatively and qualitatively. It is evident that metagenomics will be a standard tool for studying the diversity and function of microbes in the near future, as fingerprinting methods did previously. As the speed of data accumulation is accelerating, bioinformatic tools and associated databases for handling those datasets have become more urgent and necessary. To facilitate the bioinformatics analysis of metagenomic data, we review some recent tools and databases that are used widely in this field and give insights into the current challenges and future of metagenomics from a bioinformatics perspective.
Computational Biology ; Dermatoglyphics ; Ecology ; Handling (Psychology) ; High-Throughput Nucleotide Sequencing ; Metagenomics

PURPOSE: This study was to explore situations that might put the middle-aged Korean-Chinese female migrant workers at risk for work-related musculoskeletal diseases (WMSDs). At the development phase of a continuing health project, the study aimed to clarify health promotion program needs of the migrant population. METHODS: A qualitative description research design was used with three focus groups of 23 Korean-Chinese female migrant workers. Each focus group interview was conducted for 70-minutes using semi-structured interview guidelines. The data were analyzed using directed qualitative content analysis techniques. RESULTS: The majority of the participants were household workers and their work included heavy material handling, standing for a long time, and working in awkward postures. They experienced discrimination from employers, lack of control at work, limitations in open-communication, job insecurity, and acculturation. They had needs to have health promotion programs for preventing and managing chronic diseases, depression and menopause as well as WMSDs. CONCLUSION: The participants were situated in work environments with physical demanding tasks, acculturative and job-related stress and lack of opportunities to participate in health promotion programs. It is suggested to develop a comprehensive program to better meet the needs of middle-aged Korean-Chinese female migrant workers rather than targeting the reduction of WMSDs.
Acculturation ; Chronic Disease ; Depression ; Discrimination (Psychology) ; Family Characteristics ; Female ; Focus Groups ; Handling (Psychology) ; Health Promotion ; Humans ; Menopause ; Musculoskeletal Diseases ; Posture ; Research Design ; Risk Factors ; Transients and Migrants