Rise of single-case experimental designs: A historical overview of the necessity of single-case methodology.

ABSTRACTWindelband ([1894]1980) advocated that two approaches are used for accumulating scientific knowledge. The first is the idiographic approach that derives knowledge from a single unit, and the second is the nomothetic approach that accumulates knowledge of a group. Given these two approaches, the former matches case studies while the latter is more appropriate with experimental group studies. Scientists have criticized both methodologies for their various limitations. Later, the single-case methodology emerged as an alternative that potentially allays these limitations. In this context, this narrative review aims to describe the historical roots of single-case experimental designs (SCEDs) that have emerged to eliminate the tension of nomothetic and idiographic approaches over time. First, the review focuses on the emergence of SCEDs. Second, the strengths and challenges of SCEDs are reviewed, including those to address the limitations of group experimental and case studies. Third, the use and analyses of SCEDs are outlined, considering their current status. Fourth, this narrative review continues to delineate the dissemination of SCEDs in the modern scientific world. As a result, SCEDs can be evaluated as a method that has the potential to overcome the issues encountered in case description and group experimental research. Thus, that helps accumulate nomothetic and idiographic knowledge in determining evidence-based practices.

Extended Central Artery Perforator Propeller Flap for Large Nasal Defects.

Various local flaps have been defined for small skin defects of the nose. However, the repair of large nasal defects is only possible with flaps allowing a large tissue transfer, such as a free flap, forehead flap, and nasolabial flap. In this study, large nasal defects were reconstructed with extended central artery perforator propeller (CAPP) flaps in an attempt to describe a single-stage procedure as an alternative technique to the median forehead flap. Thirteen large nasal skin defects, including dorsum and nasal sidewall and/or dome, were repaired with a CAPP flap between January 2015 and March 2018. A total of 13 patients aged 19 to 92 years were included. The mean follow-up period was 14.9 months. Pathological diagnoses were basal cell carcinoma in 5 patients, squamous cell carcinoma in 6 patients, and trauma in 2 patients. Defect size ranged between 3 × 3 and 4 × 5 cm. Flap size ranged between 3 × 7 and 5 × 10 cm. No major complications including total flap failure, hematoma, or infection were observed. However, a partial flap necrosis occurred in 1 patient. In 3 patients, scar revision surgery was performed at the postoperative period. In conclusion, CAPP flap use is a safe and reliable option to repair large nasal defects. This flap is able to cover large nasal defects including dorsal, dome, and nasal sidewall defects in a single-stage procedure. Requiring no pedicle separation, this flap is an alternative option to the conventional median forehead flap.

Subunit Reconstruction of Mid-Facial Defects With Free Style Facial Perforator Flaps.

INTRODUCTION: Reconstruction of facial defects is not only important for cosmesis but also for the function. Local flaps are considered the best reconstruction method for facial defects. The authors want to show the feasibility of free style facial perforator flap for the reconstruction of moderate sized mid-facial defects. METHODS: Free style facial artery and lateral nasal artery perforator flaps were performed in 22 patients (11 males and 11 females) who had removal of facial tumor between March 2015 and December 2016 RESULTS:: The median age of patients was 62 years (range: 35-84). The mean follow-up period was 12.6 months (range: 5-24). Pathology results were basal cell carcinoma in 13 patients, squamous cell carcinoma in 6 patients, and other skin tumors in 3 patients. The defect size ranged from 2 × 2 to 5 × 5 cm. No major or minor complication happened but 1 flap had venous congestion that healed without any intervention CONCLUSION:: Free style facial perforator flaps are highly reliable flaps with wide range of motion. In addition, they provide single-stage closure with esthetic subunit reconstruction. With the current knowledge of reconstruction and skills of microsurgery, they can be easily the first choice for the closure of mid-facial defects.

A Rare Case of Endochondral Pseudocyst of the Auricle.

Endochondral pseudocyst of the auricle is a very rare, benign, non-inflammatory cystic lesion. It most commonly develops in the scaphoid or triangular fossa of the ear. In this case report, we present a 46-year-old man with a painless lesion on the scaphoid fossa of the right ear. We removed the hypertrophic perichondrium forming the anterior wall of the pseudocyst, curetted the ear cartilage, and dressed it with compression. No complications, such as infection, seroma, or hematoma, occurred during the postoperative period. A good cosmetic result was ultimately obtained. The patient experienced no recurrence within a 14-month follow-up period. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Intramuscular myxoma: clinical and surgical observation notes on eleven cases.

PURPOSE: Intramuscular myxoma (IM) is a benign, soft tissue neoplasm of mesenchymal origin. We report our experience with this tumour. METHOD: This clinical study comprised 11 cases of IM that were operated on between March 2008 and June 2016. Tumour location and size, results of pre-operative radiological studies, preop-erative biopsies, pathology examinations, applied surgical method and post-operative complications were reported for all patients. RESULTS: In total, nine patients with 11 IMs with a mean age of 60.0 years were assessed. Mean follow-up was 39.2 months. Tumours were located in the right thigh (5 patients, 7 IM), left gluteal area (2 patients, 2 IM), right gluteal area (1 IM) and left thigh (1 IM) ranging from 2 × 1 cm to 10 × 17 cm Pre-operative radiological diagnoses were cystic lesion, abscess, bursitis, fibrosarcoma, fibroma, lipoma, malign mesenchymal tumour and IM. Pre-operative biopsy was performed for five cases. All tumours were removed via simple excision and were pathologically consistent with IM. No complication or recurrence was observed during the follow-up period. CONCLUSION: IM is a relatively rare benign tumour, the pre-operative diagnosis of which using radiological and clinical methods is quite difficult, creating pre-operative diagnostic confusion. It is generally diagnosed by microscopic examination. Simple excision with a small margin of surrounding tissue is considered to be sufficient for its treatment.

Characteristics of Missing Data in Single-Case Experimental Designs: An Investigation of Published Data.

Single-case experimental designs (SCEDs) have grown in popularity in the fields such as education, psychology, medicine, and rehabilitation. Although SCEDs are valid experimental designs for determining evidence-based practices, they encounter some challenges in analyses of data. One of these challenges, missing data, is likely to be occurred frequently in SCEDs research due to repeated measurements over time. Since missing data is a critical factor that can weaken the validity and generalizability of a study, it is important to determine the characteristics of missing data in SCEDs, which are especially conducted with a small number of participants. In this regard, this study aimed to describe missing data features in SCEDs studies in detail. To accomplish this goal, 465 published SCEDs studies within the recent 5 years in six journals were included in the investigation. The overall results showed that the prevalence of missing data among SCEDs articles in at least one phase, as at least one data point, was approximately 30%. In addition, the results indicated that the missing data rates were above 10% within most studies where missing data occurred. Although missing data is so common in SCEDs research, only a handful of studies (5%) have handled missing data; however, their methods are traditional. In analyzing SCEDs data, several methods are proposed considering missing data ratios in the literature. Therefore, missing data rates determined in this study results can shed light on the analyses of SCEDs data with proper methods by improving the validity and generalizability of study results.

A Description of Missing Data in Single-Case Experimental Designs Studies and an Evaluation of Single Imputation Methods.

Missing data is inevitable in single-case experimental designs (SCEDs) studies due to repeated measures over a period of time. Despite this fact, SCEDs implementers such as researchers, teachers, clinicians, and school psychologists usually ignore missing data in their studies. Performing analyses without considering missing data in an intervention study using SCEDs or a meta-analysis study including SCEDs studies in a topic can lead to biased results and affect the validity of individual or overall results. In addition, missingness can undermine the generalizability of SCEDs studies. Considering these drawbacks, this study aims to give descriptive and advisory information to SCEDs practitioners and researchers about missing data in single-case data. To accomplish this task, the study presents information about missing data mechanisms, item level and unit level missing data, planned missing data designs, drawbacks of ignoring missing data in SCEDs, and missing data handling methods. Since single imputation methods among missing data handling methods do not require complicated statistical knowledge, are easy to use, and hence are more likely to be used by practitioners and researchers, the present study evaluates single imputation methods in terms of intervention effect sizes and missing data rates by using a real and hypothetical data sample. This study encourages SCEDs implementers, and also meta-analysts to use some of the single imputation methods to increase the generalizability and validity of the study results in case they encounter missing data in their studies.

A Meta-Analysis of Self-Management Interventions in Teaching Daily Living Skills to Autistic Individuals.

The current study aimed to conduct a systematic review and meta-analysis of self-management interventions for teaching daily living skills to autistic individuals. This study accessed the corresponding studies by doing a search in six databases. 14 articles and one dissertation met the inclusion criteria. The included studies were first analyzed descriptively and coded according to quality indicators using What Works Clearinghouse (WWC) standards. Second, the effect sizes of the included studies were calculated using two different effect size measures (i.e., Tau-U and performance-criteria-based effect size values [PCES]). Third, these analyses were also conducted for generalization and maintenance data. Of 15 studies included in this review, nine met the WWC standards with and without reservations. Tau-U analyses were conducted for 14 studies, whereas PCES values were calculated for only eight studies with mastery criteria. The findings indicated that the self-management interventions had a .93 CI95 (.80, 1) overall effect size for Tau-U with a very large effect. On the other hand, the overall effect size for the PCES values indicated a moderate effect with .99. The weighted effect sizes in generalization and maintenance phases were very large for Tau-U; however, moderate to high effects for PCES. Although self-management interventions showed diversity, one of the domains of daily living skills (i.e., community living skills) has not been studied in the field. Notably, among the studies in our review, the last ones are from 2019. Detailed findings from descriptive analyses and two different effect size calculations are discussed, and recommendations for future studies are given.

Performance criteria-based effect size (PCES) measurement of single-case experimental designs: A real-world data study.

Visual analysis and nonoverlap-based effect sizes are predominantly used in analyzing single case experimental designs (SCEDs). Although they are popular analytical methods for SCEDs, they have certain limitations. In this study, a new effect size calculation model for SCEDs, named performance criteria-based effect size (PCES), is proposed considering the limitations of 4 nonoverlap-based effect size measures, widely accepted in the literature and that blend well with visual analysis. In the field test of PCES, actual data from published studies were utilized, and the relations between PCES, visual analysis, and the 4 nonoverlap-based methods were examined. In determining the data to be used in the field test, 1,052 tiers (AB phases) were identified from 6 journals. The results revealed a weak or moderate relation between PCES and nonoverlap-based methods due to its focus on performance criteria. Although PCES has some weaknesses, it promises to eliminate the causes that may create issues in nonoverlap-based methods, using quantitative data to determine socially important changes in behavior and to complement visual analysis.

Validity and Reliability Analysis of the PlotDigitizer Software Program for Data Extraction from Single-Case Graphs.

Access to raw data of graphs presented in original articles to calculate the effect size of single-case research is a challenge for researchers conducting studies such as meta-analysis. Researchers typically use data extraction software programs to extract raw data from the graphs in articles. In this study, we aimed to analyze the validity and reliability of the PlotDigitizer software program, which is widely used in literature and an alternative to other data extraction programs, on computers with different operating systems. We performed the digitization of 6.846 data points on three different computers using 15 hypothetical graphs with 20 data series and 186 graphs with 242 data series from 29 published articles to accomplish the goal. Besides, using the values we digitized, we recalculated the 23 effect sizes presented in the original articles for validity analysis. Based on our sampling, we calculated intercoder and intracoder Pearson correlation coefficients. The results showed that PlotDigitizer could be an alternative to other programs as it is free and can run on many current and outdated systems, and it is valid and reliable as it is nearly perfect. Based on the obtained results and considering the data extraction process, we presented various recommendations for the researchers that will use the PlotDigitizer program for the quantitative analysis of single-case graphs.