Bias in indirectly adjusted comparisons due to taking the total study population as the reference group

1987 ◽  
Vol 6 (2) ◽  
pp. 193-195 ◽  
Author(s):  
Sander Greenland
2005 ◽  
Vol 44 (02) ◽  
pp. 56-61 ◽  
Author(s):  
G. Wunderlich ◽  
Th. Grüning ◽  
R. Koch ◽  
H. Döge ◽  
J. Kotzerke ◽  
...  

SummaryThe upper limit of the TSH reference range is currently under discussion. In its recent guidelines, the National Academy of Clinical Biochemistry (NACB) recommended the use of ~2.5 mIU/L, rather than ~4 mIU/L, due to the fact that reference populations, on which the definition of the reference range is based, contain persons undergoing an initial phase of autoimmune thyroid disease. This will skew the upper reference limit of TSH. Ultrasonography, in addition to measurement of thyroid autoantibodies, should be used to exclude these persons. Objective: The present study investigates whether the NACB recommendation also applies for a region of mild iodine deficiency. Methods: According to NACB criteria, a reference population (713 persons) was defined out of a total study population of 1442. The TSH reference range was calculated in this reference group and in further subgroups by percentiles. The results were compared with the total study population and the NACB recommendation. All assays used were provided by BRAHMS Diagnostica AG, Hennigsdorf, Germany. Results: As expected, all median TSH values, excluding the median of the group with a hypoechogenic thyroid were close to 1.2 mIU/L. The 97.5th percentile in the reference population was 3.35 mIU/L. However, there was no difference compared to the total study population. Conclusion: The upper reference limit for TSH based on a reference population according to NACB criteria came down to 3.35 mIU/L, but not to ~2.5 mIU/L. Interestingly, there is no difference compared to the total study population.


Author(s):  
Petra C. Vinke ◽  
Milou H. H. S. Luitjens ◽  
Karlien A. Blijleven ◽  
Gerjan Navis ◽  
Daan Kromhout ◽  
...  

Abstract The identification of early-life determinants of overweight is crucial to start early prevention. As weight gain accelerates between 2 and 6 years, we studied the association between diet quality in children aged 3 years and the change in BMI and overweight incidence in the following 7 years. From the Dutch GECKO Drenthe birth cohort, 1001 children born in 2006 or 2007 with complete data on diet (food frequency questionnaire at the age of 3 years) and growth at the age of 3 and 10 years were included. Diet quality was estimated with the evidence-based Lifelines Diet Score (LLDS). Measured height and weight at the age of 3 and 10 years were used to calculate BMI z-scores standardized for age and sex. The associations of the LLDS (in quintiles) with BMI-z change and overweight incidence were studied with linear and logistic regression analyses. Overweight prevalence in the total study population increased from 8.3% at the age of 3 years to 16.7% at the age of 10 years. The increase in overweight prevalence ranged from 14.7% in Q1 to 3.5% in Q5. Children with a better diet quality (higher quintiles of LLDS) increased significantly less in BMI-z (confounder adjusted βLLDS = −0.064 (−0.101; −0.026)). Children with a poor diet quality at the age of 3 years had a considerably higher risk for overweight at the age of 10 years (confounder adjusted OR for Q1 vs. Q5 was 2.86 (95% CI 1.34–6.13). These results show the importance of diet in healthy development in the early life following the first 1000 days when new habits for a mature diet composed of food groups with lifelong importance are developed, providing a relevant window for overweight prevention early in life.


2021 ◽  
Vol 11 (1) ◽  
pp. 46-48
Author(s):  
Nidhi Giri ◽  
Anand Acharya ◽  
Kanika Yadav

Introduction: Various forms of malocclusion are a matter of serious concern in Nepalese population. This study was carried out to understand the prevalence of malocclusion among the school children of Biratnagar. The objective of this research is to find out the prevalence of malocclusion of children from different schools of Biratnagar visiting the Pedodontics and Orthodontics department of Nobel Medical College and Teaching Hospital, Biratnagar. Materials and Method: A descriptive cross sectional study method was used in this research. Data was collected by using direct observation of the subjects and occlusal assessment was done according to Angle’s classification and Dewey’s modification types of class I, class II and class III malocclusion. Result: Subjects with normal occlusion was found to be 39 % and with malocclusion was found to be 61%. Among them, class I malocclusion (60%) and angles class II div I subjects (88.33%) were in majority of the total study population. Conclusion: The present study helps to determine the prevalence of malocclusion and need of orthodontic treatment for the school children of Biratnagar


2015 ◽  
Vol 11 (1) ◽  
pp. 6-8
Author(s):  
S Dahal ◽  
SK Agrawal ◽  
A Shrestha ◽  
TK Bhagat

Background and Objectives: Increased concern over dental appearance has been observed during childhood and adolescence to early adulthood. The study was conducted with objectives to assess the self-perception of dental aesthetics, knowledge, attitude and management of dental trauma and halitosis.Materials and Methods: Self-administered questionnaire translated in Nepali language consisting of 32 questions was used. The completed questionnaires were analyzed using descriptive statistics.Results: Out of the total study population, 63% were satisfied with their overall tooth appearance and 71.7% with their tooth color. Twenty-nine percent had experienced dental trauma. More than half of the study population thought that immediate treatment was required after dental trauma. Fifty seven percent of the villagers had halitosis.Conclusion: The research clearly shows that the people of Aurabani VDC were satisfied with their tooth color and overall tooth appearance; however the knowledge regarding emergency management of dental trauma, the cause and management of halitosis was insufficient.JCMS Nepal. 2015;11(1):6-8


2018 ◽  
Vol 7 (1) ◽  
pp. 4-9
Author(s):  
Md Mahamudur Rahman ◽  
Md Akram Hossain ◽  
Shyamal Kumar Paul ◽  
Salma Ahmed ◽  
Md Murshed Alam ◽  
...  

Soil transmitted helminthes (STHs) infections are common throughout the tropics and subtropics and represents a major public health problem in developing countries. The rate of STHs infection found in the present study was very high in comparison to other countries of this Subcontinent, though they are taking antihelmintics every 6 months interval under Government National Health Program. The present study was carried out to see the Prevalence of STHs infection among the school children in Mymensingh, Bangladesh. A total of 500 stool samples from healthy individuals were collected during April, 2012 to February, 2013 from 20 schools comprising 10 rural and 10 urbans under Sadar upazila, Mymensingh, Bangladesh. The samples were examined in the department of Microbiology, Mymensingh Medical College using saline and iodine preparation microscopy and McMaster technique for the detection of ova of STHs.  The STHs prevalence irrespective of the age and sex of the individuals were 37.0% (185) out of 500 specimens where 68.0% (340/500) individuals were male represents the prevalence 38.0% (129/340) and 32.0% (160/500) individuals were female represents the prevalence 35.0% (56/160). Majority of the cases belonged to the age group >5-10 years 50.2% (251/500) of the total, constituted the prevalence 20.2% (101/500) of the total population and 40.2% (101/251) of the individual age group. The distribution of different STHs with their prevalence in the study population where Ascaris lumbricoides (AL) was 63.8% (118), Trichuris trichiura (TT) 37.3% (69), Enterobius vermicularis (EV) 8.1% (15), Ancylostoma duodenale (AD) 7.5% (14), and mixed infection was 15.1% (28). The upper socio-economic class constituted 5.0% (25/500) of the total study population with the prevalence of 20.0% (5/25). The middle socio-economic class constituted 50.0% (250/500) of the total study population with the prevalence of 37.2% (93/250) and the lower socio-economic class constituted 45.0% (225/500) of the total study population with the prevalence of 38.6% (87/225). The urban population constituted 34.0% (170/500) of the total population representing the prevalence 31.2 % (53/170) and rural population constituted 66.0% (330/500) of the total population representing the prevalence 40.0% (132/330).  In this study, STHs detection by McMaster method was satisfactory. Thereby, McMaster method could be adapted for rapid detection and quantification of STHs. Moreover, one more frequent administration of antihelmintics with close monitoring of drug administration may reduce the prevalence of STHs infection in Bangladesh. CBMJ 2018 January: Vol. 07 No. 01 P: 04-09


2012 ◽  
Vol 13 (2) ◽  
pp. 173-177 ◽  
Author(s):  
Farideh Bahrani ◽  
Parnian Ghadiri ◽  
Mahroo Vojdani

ABSTRACT Aim The aim of this study was to define the prevalence and severity of temporomandibular disorders (TMD) among Iranian dental and nondental students who attended Shiraz University of Medical Sciences. Materials and methods The samples consisted of 200 subjects, 100 dental and 100 nondental students (equal distribution between males and females). Subjects ages ranged from 18 to 30 years (24.07 ± 2.93). A functional evaluation was performed using the Helkimo dysfunction index (Di). Data were evaluated by the Chi-square test. Results Among the total study population, 71% showed some degree of dysfunction. Prevalence ratio in dental students was 80%, while in nondental students was 62% (p < 0.05, odds ratio = 0.679). With respect to gender, women (80%) were more affected than men (62%). A significant relationship was found between gender and the occurrence of TMD (p < 0.05). Conclusion A high prevalence of signs of TMD in Iranian university students was seen which was greater in dental students and women. Clinical significance The results of this study showed that the prevalence of TMD among dental students and women was significantly higher than nondental students and men. These findings might be due to poor postural style or emotional stress during dental practice. How to cite this article Bahrani F, Ghadiri P, Vojdani M. Comparison of Temporomandibular Disorders in Iranian Dental and Nondental Students. J Contemp Dent Pract 2012;13(2): 173-177.


2021 ◽  
Vol 9 (09) ◽  
pp. 961-972
Author(s):  
K. Shivaraju ◽  
◽  
Karanam Sai Arun ◽  
Mandhala Saikrishna ◽  
◽  
...  

Background: Anemia is often considered as a normal physiological process that occurs with aging. but recently since past 2 decades anemia of any degree is being recognized as significant independent contributor to morbidity mortality and frailty in elderly patients. It is easy to overlook anemia in elderly as symptoms of anemia like fatigue, SOB etc are often attributed to aging process itself. many evidences accumulated states that anemia of any degree reflects poor health and increased vulnerability to poor outcomes. Materials and methods: This study was conducted in the department of internal medicine in a tertiary care hospital over a period of one year with sample size of 362 subjects satisfying the inclusion and exclusion criteria after taking the consent form. Results: Moderate degree anaemia was the commonest around, 65.6% followed by severe degree anemia 20.1%. Easy fatigability was the commonest symptom and pallor was the commonest sign of anaemia in elderly. Anemia is not always a consequence of aging. Anemia of unexplained etiology constituted 15.97% of total study population. Conclusion: Anaemia in elderly is a challenge and has to be approached in an organized manner for appropriate diagnosis and evaluation to look into its cause and plan management to improve the quality of life of the elderly persons.An effort should always be made to reach etiological diagnosis before instituting specific therapy.


Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2602
Author(s):  
Shihab Kochumon ◽  
Hossein Arefanian ◽  
Sardar Sindhu ◽  
Steve Shenouda ◽  
Reeby Thomas ◽  
...  

Steroid receptor RNA activator 1 (SRA1) is involved in pathophysiological responses of adipose tissue (AT) in obesity. In vitro and animal studies have elucidated its role in meta-inflammation. Since SRA1 AT expression in obesity/type 2 diabetes (T2D) and the relationship with immune-metabolic signatures remains unclear, we assessed AT SRA1 expression and its association with immune–metabolic markers in individuals with obesity/T2D. For this, 55 non-diabetic and 53 T2D individuals classified as normal weight (NW; lean), overweight, and obese were recruited and fasting blood and subcutaneous fat biopsy samples were collected. Plasma metabolic markers were assessed using commercial kits and AT expression of SRA1 and selected immune markers using RT-qPCR. SRA1 expression was significantly higher in non-diabetic obese compared with NW individuals. SRA1 expression associated with BMI, PBF, serum insulin, and HOMA-IR in the total study population and people without diabetes. SRA1 associated with waist circumference in people without diabetes and NW participants, whereas it associated inversely with HbA1c in overweight participants. In most study subgroups AT SRA1 expression associated directly with CXCL9, CXCL10, CXCL11, TNF-α, TGF-β, IL2RA, and IL18, but inversely with CCL19 and CCR2. TGF-β/IL18 independently predicted the SRA1 expression in people without diabetes and in the total study population, while TNF-α/IL-2RA predicted SRA1 only in people with diabetes. TNF-α also predicted SRA1 in both NW and obese people regardless of the diabetes status. In conclusion, AT SRA1 expression is elevated in people with obesity which associates with typical immunometabolic markers of obesity/T2D, implying that SRA1 may have potential as a biomarker of metabolic derangements.


Hypertension ◽  
2021 ◽  
Vol 77 (3) ◽  
pp. 919-928
Author(s):  
So-Ryoung Lee ◽  
Chan Soon Park ◽  
Eue-Keun Choi ◽  
Hyo-Jeong Ahn ◽  
Kyung-Do Han ◽  
...  

The association between the cumulative hypertension burden and the development of atrial fibrillation (AF) is unclear. We aimed to investigate the relationship between hypertension burden and the development of incident AF. Using the Korean National Health Insurance Service database, we identified 3 726 172 subjects who underwent 4 consecutive annual health checkups between 2009 and 2013, with no history of AF. During the median follow-up of 5.2 years, AF was newly diagnosed in 22 012 patients (0.59% of the total study population; 1.168 per 1000 person-years). Using the blood pressure (BP) values at each health checkup, we determined the burden of hypertension (systolic BP ≥130 mm Hg or diastolic BP ≥80 mm Hg), stratified as 0 to 4 per the hypertension criteria. The subjects were grouped according to hypertension burden scale 1 to 4: 20% (n=742 806), 19% (n=704 623), 19% (n=713 258), 21% (n=766 204), and 21% (n=799 281). Compared with normal people, subjects with hypertension burdens of 1, 2, 3, and 4 were associated with an 8%, 18%, 26%, and 27% increased risk of incident AF, respectively. On semiquantitative analyses with further stratification of stage 1 (systolic BP of 130–139 mm Hg or diastolic BP of 80–89 mm Hg) and stage 2 (systolic BP ≥140 mm Hg or diastolic BP ≥90 mm Hg) hypertension, the risk of AF increased with the hypertension burden by up to 71%. In this study, both a sustained exposure and the degree of increased BP were associated with an increased risk of incident AF. Tailored BP management should be emphasized to reduce the risk of AF.


Author(s):  
Shilpa Atwal ◽  
Jitender Thakur

Background: To study the use of guidelines in statins prescription at tertiary care centre of North India Methods: Study was conducted on Patients with indications for statins presenting to cardiology OPD,Medicine OPD and Endocrinology OPD and started on statins at PGIMER, Chandigarh, within a period of 9 months. Results: In our study, 81.9% of total study population were receiving statins according to guideline and 18.1% were receiving statins not according to guideline. In the primary prevention group,91(83.5%) patients were receiving statins according to guideline and 18(16.5%) were receiving not according to guideline. In the secondary prevention group, 108(80.6%) patients were receiving statins according to guideline and 26(19.4%) patients were receiving statins not according to guideline. Concluded: In our study, more than two third of patients in our study were receiving prescriptions according to guideline Keywords: Statin, Guideline, Use


Sign in / Sign up

Export Citation Format

Share Document