Research Article

Validity and Reliability of the Turkish Version of Pittman Ostomy Complication Severity Index

10.4274/tjcd.galenos.2019.2019-9-5

  • Ahu Uzun Arslantaş
  • Elif Karahan
  • Mustafa Çağatay Büyükuysal

Received Date: 18.10.2019 Accepted Date: 05.11.2019 Turk J Colorectal Dis 2020;30(1):27-36

Aim:

This study aimed to investigate the reliability and validity of the Turkish version of the Pittman Ostomy Complication Severity index.

Method:

This methodological research was carried out between January 1, 2017, and January 1, 2018, at the Stomatherapy Unit of a Health Practice and Research Center in the Western Black Sea Region. The sample of the study consisted of 90 patients with an ostomy who had colostomy and ileostomy for at least one month. Stoma Individual Follow-up Form and Pittman Ostomy Complication Severity Index form were used in the study. Preoperative demographic characteristics, stoma-related characteristics within the first 24 hours after surgery, and 30 days postoperatively were evaluated according to the Pittman Ostomy Complication Severity Index. SPSS 19.0 and Excel 2016 software were used for statistical analysis.

Results:

The mean age of patients was 60.22±13.23 years. It was determined that 44.4% of the patients were women, and 55.6% were men. Of all patients, 90% were married, 71.1% were primary school graduates, and 41.1% were housewives. Translation-back translation was performed for the language validity of the index. Content validity was taken from 11 experts, and Content Validity Index was determined to be 0.95. Complication-related parameters for the construct validity of the index were calculated from the significance of the total score of the Pittman Ostomy Complication Severity index. The reliability of the Pittman Ostomy Complication Severity index was evaluated with the compliance between independent observers. The linguistic compliance, which was evaluated with the compliance between observers in expert opinions, was significant (p<0.001; Kendall’s W=0.131; chi-square: 66.668). The content compliance, which was evaluated with the compliance between observers in expert opinions, was significant (p<0.001; Kendall’s W=0.132; chi-square: 67.529).

Conclusion:

We showed that the Turkish version of the Ostomy Complication Severity index is a valid and reliable tool for evaluating the severity of complications in individuals with an ostomy. This index can also be used to identify and measure the severity of early complications in patients with an ostomy.

Keywords: Colostomy, ileostomy, complication, nursing care

Introduction

The stoma that has been created to eliminate the underlying pathology and improve the patient’s condition affects the whole life of the individuals. The stoma causes a variety of physiological, psychological, and social problems to the individual from the first time to the post-discharge period and thus adversely affects the adaptation process to life.1 Despite the development of surgical methods and precautions taken, it is observed that the rate of complication development after stoma is high. Complications of the stoma may occur due to surgical intervention, underlying pathology, insufficient preoperative, and postoperative treatment and care.2,3,4

Complications related to stoma can be a dull discomfort or a severe life-threatening problem. Complications are classified as early and late complications depending on the time of occurrence. It has been reported that early stoma complications are seen mainly in cases where the stoma region cannot be marked in emergency conditions or in case of technical errors. Ischemia and stoma necrosis, peristomal skin problems, and mucocutaneous separation develop in the early period. Late complications are usually seen in permanent stomas and can be listed as parastomal hernia, stomal prolapse, stenosis, and peristomal dermatitis.2,5,6 The incidence of stoma complications varies, and the rate is reported to be between 10% and 70%.7,8,9,10 It is stated that complication rates increase in emergency surgical procedures, and these rates are higher in individuals who do not have stoma sites marked than those who are marked.2,8,9 The incidence of stoma complications is related to the follow-up frequency of patients with a stoma, and the incidence of stoma complications decreases as the frequency of follow-up increases. Studies have reported a 6-fold reduction in the risk of complications associated with the care provided by the stoma team.11,12,13 The main goal of stoma care should be to support individuals with a stoma to adapt to the new lifestyle, to accept the image change in their body, and to be able to continue their life independently. Stoma and wound care nurses are responsible for the prevention and early recognition of complications and differentiating factors causing complications.14 Therefore, monitoring of complications is essential in terms of nursing care outcomes. The tools with proven validity and reliability for the monitoring of stoma complications are limited in Turkey.3 The Pittman Ostomy Complicity Severity index (OCSI) was developed by Joyce Pittman to identify and assess the severity of complications during the follow-up period (30 days postoperatively) of patients with a stoma.4

This study aimed to evaluate the validity and reliability of the Turkish version of OCSI, which was prepared originally  in English for patients with a stoma.


Materials and Methods

Type of research: Methodological research.

Time and Place of the Study: The research was conducted between January 1, 2017, and January 2018 at the Stomatherapy Unit of an Application and Research Center in the Western Black Sea Region. In the stomatherapy unit, training, counseling, and care services are provided to the individual with a stoma and his family by the researcher who has stomaterapy nursing certificate.

Population and Sample of the Study: The study population consisted of individuals who had colostomy and ileostomy for at least one month and who applied for treatment to the study centre during the study period. Inclusion criteria included being 18 years of age or older, having no hearing and speech problems, not having any cognitive problems preventing him/her from expressing himself/herself, having a stoma (colostomy, ileostomy) for one month (30 days), not having a psychiatric diagnosis and volunteering to participate in the study. One of the methods recommended in the determination of sample size in validity and reliability studies is the presence of at least 10 participants per item.15 In this research, this method was adopted, and 90 individuals with stoma were recruited.


Data Collection Tools

Stoma Follow-up Form and Turkish version of OCSI were used to collect data. This index is a tool used by the doctor or nurse to assess the individual with an ostomy.

Stoma Follow-up Form: This form, which was formed in accordance with the related literature16, included following data: The socio-demographic characteristics of the individuals with stoma, being informed about stoma and surgery, and stoma site marking status in the preoperative period, chemotherapy/radiotherapy status and whether the surgery was urgent or planned, and surgery, type of stoma, duration of stoma, stoma region, stoma color, stoma moisture, stoma height, stoma shape, peristomal skin, stoma diameter, presence of baguette, presence of bleeding, mucocutaneous separation status in the postoperative period (within the first 24 hours), and whether there were stoma care-related impeding conditions.

Pittman Ostomy Complication Severity Index: OCSI was developed by Joyce Pittman in 2014 to assess the frequency and severity of early postoperative complications during follow-up (30 days postoperatively) in individuals with a stoma. The OCSI demonstrated acceptable evidence of content validity index [(CVI)=0.9)], interrater reliability for individual items (k=0.71-1.0), and almost perfect agreement for total scores among raters (ICC=0.991, p≤.001).4 This index evaluates leakage, peristomal irritant dermatitis, pain, bleeding in or around the stoma, stomal necrosis, stenosis, retraction, mucocutaneous separation, and hyperplasia. All complications are scored 0 to 3 (0=none, 1=mild, 2=moderate, 3=severe) with a Likert-like scale. The total score ranges between 0 and 27. Higher scores indicate more severe ostomy complications.4


Study Process

The original version of the index was obtained from Dr. Joyce Pittman by establishing communication via e-mail, and we gained permission for using a Turkish version of OSCI for a validity and reliability study. The following steps were taken in order to conduct the validity and reliability study of the scale with the patients in the study cohort:

• Language and content validity of the index were examined,

• For language validity, the index was translated from English to Turkish by two medical experts with extensive knowledge of English, and then translated from Turkish to English by one medical expert with extensive knowledge of English without seeing the original English version,

• 11 experts were consulted for content validity,

• The Turkish version of the index was finalized,

• Following finalizing the index after expert opinions, it was applied as pre-application to five individuals included in the study,

• Data were collected by face-to-face interview method and physical evaluation before and 30 days postoperatively from individuals who met the inclusion criteria.


Evaluation of Data

SPSS 19.0 and Excel 2016 software were used for statistical analysis. Descriptive data were shown with numbers, percentage, mean, standard deviation, median, minimum, and maximum values. The suitability of continuous variables to normal distribution was examined by the Shapiro-Wilk test. Mann-Whitney U test and Kruskal-Wallis test were used for comparison of variables that did not meet normal distribution. The relationships between quantitative variables were analyzed by the Spearman correlation coefficient. Pearson chi-square test was used to compare qualitative variables between groups. The agreement between the expert opinions was examined by the Kendall W coefficient. p<0.05 was considered statistically significant.


Ethical Aspects of Study

Permission was granted from Joyce Pittman to use OCSI in the study. Permission was obtained from the Non-Interventional Clinical Research Ethics Committee of a University in the Western Black Sea Region (Date: 30.11.2016 No: 5/14). Written permission was obtained from the institution for the implementation of the study. The purpose of the study was explained by the researcher, and informed consent was obtained from the individuals willing to participate in the study.


Results


Evaluation of Descriptive Characteristics of Individuals with Stoma

The mean age of the participants was 60.22±13.23 years, and the mean body mass index was 25.42±7.5. Of all participants, 55.6% were male, 71.1% were primary school graduates, 50% were retired, 90% were married, 93.3% had social insurance coverage, and 94.4% were living with their families. The medical diagnosis of patients was colon cancer in 35.6%, rectal cancer in 26.7%, and other malignancies and diseases in 37.8%. It was determined that 53.3% had a chronic disease, 74.4% had previous surgical operation, and 16.7% had a regular smoking habit (Table 1). It was determined that 58.9% of the stoma sites were marked before the surgery and that patients were informed about surgery. There were no impeding conditions to stoma care in all patients, and 15.6% of the patients received neoadjuvant therapy before surgery. It was found that 41.1% of the individuals in the study were operated urgently, and 58.9% of them were scheduled for surgery (Table 2).

In the evaluation results of individuals within the first 24 hours after surgery, it was found that 36.7% underwent colostomy, 37.8% underwent loop colostomy, 68.9% had a temporary stoma, and 58.9% had stoma in the left lower quadrant. It was determined that stoma color was pale pink in 63.3%, the stoma was moist in 96.7%, stoma height was prolapsed in 87.8%, the stoma was round in 73.3%, and peristomal skin was soft in 70%. The mean stoma diameter of the subjects was 43.93±5.33 mm. In the first 24 hours postoperatively, all individuals in the study group were found to have no bleeding and mucocutaneous separation of the stoma (Table 3).


Language Validity of Pittman Ostomy Complication Severity Index

In order to determine the validity and reliability of OCSI, firstly, language validity studies were conducted. First, the index was translated from English to Turkish by two experts in the field of medicine. In the last step, the back-translation (Turkish to English) was performed by an expert in the field of medicine. The index was compared with the statements in the original form and presented to the expert opinion of 11 faculty members in the nursing and medical departments. Experts were asked to evaluate each item from 1 to 4 using a Likert-like scale for clarity of items [1= Major revision required (as suggested), 2= Minor revision required (as suggested), 3= Relevant, 4= Very relevant]. Following the recommendations of the experts, the scale items with a value of 1 and 2 were reviewed, and corrections were made, and the scale was finalized. When the analyzes of the scores given by the experts for OCSI language validity were evaluated, content validity ratio (CVR) was 0.59, and CVI was 0.954.


Content Validity of Pittman Ostomy Complication Severity Index

In the content validity study of the index, it was aimed to determine whether the items in the index were appropriate for their purpose, whether they represented the content to be evaluated, whether they were related to the problem adopted and whether they contained different concepts outside the content. As for language validity, the same experts were asked to score by using a 4-point Likert-like scale. When the scores of experts given for OCSI content validity were analyzed, CVR was 0.59, and CVI was 0.971 (Table 4).


Reliability Analysis of Pittman Ostomy Complication Severity Index

The reliability of the index was evaluated by the agreement between the independent observers, and there was agreement in terms of language (p<0.001; Kendall’s W=0.131; chi-square=66.668) and content (p<0.001; Kendall’s W=0.132; chi-square=67.529).


Comparison of Socio-demographic and Clinical Characteristics of Patients with Total Score of Pittman Ostomy Complication Severity Index

When OCSI total score and sociodemographic and clinical characteristics of subjects were compared, the total OCSI score was significantly higher in the case of female gender (p = 0.046), stoma in the right lower quadrant (p=0.038) and baguette (p=0.011). It was found that the difference was not significant regarding the type of surgery, information about stoma, stoma marking, surgery performed, type of stoma, and duration of the stoma (Table 5).


Discussion

A stoma is opened in order to ensure the continuity of the system and improve the quality of life of individuals with problems related to the gastrointestinal system. It is a condition that both changes the lifestyles of individuals and affects the quality of their lives. It is essential to prevent complications in temporary or permanent stomas and to ensure that they do not adversely affect the quality of life. Although colon cancers are the most common cause of stoma, they can be created because of colon obstructions and diseases such as Fournier gangrene.6,17,18,19,20 In this study, the stoma was created due to colon and rectal cancer in the majority of patients. This is in parallel with the literature.

The validity and reliability of some tools have been made for the problems that patients with a stoma may experience in the long term. Often, these tools are intended to measure the quality of life of patients.17,21,22,23 However, valid tools for evaluating patient outcomes in the early postoperative period are very limited. In this study, it was evaluated whether or not the Turkish version of OCSI is a valid and reliable tool to follow up on the complications 30 days after stoma surgery.

While adapting a scale, it is necessary to investigate whether that scale is necessary for that society. The most important basic features sought in scales are validity and reliability. Reducing errors in both features can improve both the validity and reliability of the scale.24 Validity is the ability of the scale to accurately measure the property it aims to measure without confusing it with other features. Since validity is the degree to which a scale serves the purpose for which it is used, the measurement validity will vary depending on the purpose for which the measurements to be obtained are used. The validity of a scale cannot be determined solely by itself. It also depends on the purpose of use of the scale, the group to which it is applied, the way it is applied, and scoring. The validity of a scale is calculated by calculating the validity coefficient of that scale. This coefficient is the relationship between the values ​​obtained from the scale and the values ​​determined in accordance with the purpose of use of the scale. This value is between “-1.00” and “+1.00. The increased coefficient means that the scale serves the purpose more.25 Content validity indicates whether the items of the scale are sufficient in terms of quality and quantity of the characteristics or behaviors that they want to measure. The agreement or disagreement between expert opinions, such as the comprehensibility of the items and their suitability to the intended audience, are used as a prediction for the validity of the content or construct.26 Expert opinion is consulted to test face validity and content validity. The expert is asked to evaluate the items of the test in terms of content validity. Different methods can be used to evaluate expert opinion. The Lawshe technique is used to obtain opinions from a minimum of 5 and a maximum of 40 experts. The CVR is obtained by gathering expert opinions. The formula of CVR is CVR=(Ne/N/2)-1, in which the Ne is the number of experts indicating “essential” to an item, and N is the total number of experts who have expressed an opinion about an item.27 The other method is the Davis technique. With this technique, expert opinions for each item are graded as a) very relevant, b) relevant but need minor revision, c) item need major revision, d) not relevant. With this technique, the number of experts choosing options (a) and (b) is divided by the total number of experts to CVI. CVI is obtained over the means of the items’ total CVR (26). In this study, the opinions of 11 experts were taken in terms of language and content. CVRs were calculated as a result of expert opinions. In terms of language and content validity, CVR was found to be 0.59. CVI was calculated as a result of expert opinions. CVI was 0.954 in language validity analysis and 0.971 in content validity analysis. In this sense, the index was found to be valid in terms of Turkish language and content.

Reliability is the ability of a scale to measure (error-free measurement) close to the actual size of the particular feature. In other words, reliability is the level of consistency between different measurement results of a scale. It is necessary to be confident that the data provided by the scale is stable and that the same results will be obtained in a second measurement for the same purpose. The unreliable scale is useless.25 The Kendall’s W test, which is used to evaluate the similarity of the evaluation results of multiple observers evaluating the same subject, was used in the reliability analysis of the index. In order to see the agreement between the opinions of the experts, it was evaluated whether there is an agreement in terms of language and content. Kendall’s W value of 0.131 in terms of language and 0.132 in terms of content confirmed that expert opinions were consistent and reliable.

A stoma can be created for any reason, either urgently or planned, and postoperative complications may occur, no matter how much precautions have been taken. Creating a stoma in an emergency setting increases the risk of peristomal complications, and the risk of complications increases by up to 18%.28 In a prospective single-center study, including 192 patients, Parmar et al.11 reported that 22% of patients developed complications after elective surgery and 46% after emergency surgery. Stoma site marking in the preoperative period facilitates compliance, improves quality of life, and reduces complication rates.8 The stoma site should be marked even in an emergency setting. The common recommendations of the American Society of Colon and Rectal Surgeons and Wound, Ostomy, and Continence Nurses Society are to mark the stoma site by the surgeon or stoma nurse before the surgical procedure in all individuals who will undergo bowel operation.29,30 If preoperative stoma site marking is not possible and the patient is obese, the stoma should be placed high above the abdomen from the subcostal region. This helps the patient to see the stoma more clearly.11 In a study including 593 patients, Ratliff et al.31 reported that 95 of 292 individuals who were evaluated by the stoma nurse before surgery had postoperative complications, and 131 of 301 patients who had no preoperative evaluation were reported to have complications. Kozan and Gültekin32 found that the only factor that can be controlled in reducing the risk of parastomal hernia was the marking of the stoma site in the preoperative period. In this study, it was seen that all patients who underwent elective surgery (58.9%) were evaluated by the surgeon or stoma nurse, and the marking was performed, but that marking was not performed in emergency patients. Also, there was no significant difference in the severity of complications according to the type of surgery, information about stoma, stoma marking, surgery performed, type of stoma, and duration of the stoma. Risk factors for stoma complications include gender, body mass index, short mesentery, type of stoma, and abdominal features in the stoma site.8,9,10,11 In this study, it was found that the severity of complications was significantly higher in the female gender, stoma created in the right lower quadrant, and in the case of baguette. Although studies on gender are limited in the literature, the female gender is the predisposing factor in the parastomal hernia.32,33,34 The intestinal segment to be used for the stoma, age of the patient, the reason for the stoma, comorbid diseases, habits of the patient, and body structure are essential in determining the stoma site.35 The type and location of the stoma directly affect the complications, and the highest complication is seen in loop ileostomy.35,36,37 Another complication is retraction with a 6-10% incidence due to early removal of baguette used in loop stoma and intestinal dysfunction.7 A stoma is a very important condition that affects the life of individuals in physiological, psychological, and social aspects, so it is essential to pay attention to risk factors in order to avoid complications.


Conclusion

This study concluded that OCSI is a valid and reliable tool for assessing the severity of early complications of a stoma. As it is easy and practical to use, it guides health professionals in diagnosing and treating early complications. Accordingly, we recommend using this index in the follow-up of individuals with an ostomy.


Acknowledgement: We would like to thank Assoc. Prof. Dr. Fatma Ayça Gültekin for her contributions during the process of collecting the data.

Ethics

Ethics Committee Approval: Permission was obtained from the Non-Interventional Clinical Research Ethics Committee of a University in the Western Black Sea Region (Date: 30.11.2016 No: 5/14).

Informed Consent: The purpose of the study was explained by the researcher, and informed consent was obtained from the individuals willing to participate in the study.

Peer-review: Externally peer reviewed.

Authorship Contributions

Surgical and Medical Practices: A.U.A., Concept: A.U.A., E.K, M.Ç.B., Design: A.U.A., E.K., M.Ç.B., Data Collection or Processing: A.U.A., Analysis or Interpretation: E.K., M.Ç.B., Literature Search: A.U.A., E.K., Writing: A.U.A, E.K., M.Ç.B.

Conflict of Interest: No conflict of interest was declared by the authors.

Financial Disclosure: The authors declared that this study received no financial support.

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