General Linear Model Test Research Articles

Acute effects of exercise and active video games on adults’ reaction time and perceived exertion

The purpose of the present study was to examine the acute effects of resting, aerobic exercise practised alone, and aerobic exercise with active video games (AVG), on complex reaction time (CRT) and the post-exercise acute rate of perceived exertion (RPE) in young healthy adults. The experimental group was composed of 92 healthy young adults, 78 males and 13 females (age M = 21.9 ± 2.7 years) who completed two sessions, A and B. In session A, participants rode 30 min on an ergometer, while in session B they exercised for 30 min on an ergometer while playing an AVG on a Wii. The control group was composed of 30 young adults, 26 males and 4 females (age M = 21.4 ± 2.9 years) who rested for 30 min. In each session, a CRT task was performed before and after exercising or resting, and post-exercise global RPE was noted. Repeated measures general linear model (GLM) and Wilcoxon tests were performed. (1) Both aerobic exercise alone and aerobic exercise combined with AVG improved CRT, while resting did not; (2) aerobic exercise combined with AVG did not improve CRT more than aerobic exercise only; and (3) RPE was lower after aerobic exercise combined with AVG compared with aerobic exercise only. In young adults, exercise produces acute benefits on CRT, and practising exercise with AVG helps to decrease RPE.

Readiness for interprofessional learning among healthcare professional students.

ObjectivesThe purpose of this study was to investigate attitudes toward interprofessional learning among first year medical, nursing, and physician associate students at an American university at the start of their training. MethodsFirst year medical (n=101), nursing (n=81), and physician associate (n=35) students were invited to complete an anonymous online survey which included items related to demographic information and the Readiness for Interprofessional Learning Scale. Scores were compared by the general linear model and Duncan’s multiple range test while controlling for demographic differences. ResultsAll three groups scored in the high range, indicating readiness for shared learning. Female students, those with advanced degrees, and those with healthcare experience prior to enrolment in health professional school had significantly higher scores than their counterparts. After controlling for differences in demographic factors, nursing students scored significantly higher than physician associate and medical students (F (2,162) = 6.22, 0.0025). ConclusionsHealth professions students demonstrated readiness for interprofessional learning early in their academic programs, however important differences in baseline readiness emerged. These findings suggest that educators consider baseline attitudes of students when designing interprofessional education curricula, and use caution when extrapolating data from other geographies or cultures.

Physical Activity Level Is Associated With Maintaining Anthropometric Improvements Among Participants in a Worksite Wellness Program.

Background. Physical activity (PA) can facilitate weight loss, help avoid weight regain, and improve body composition. This study examined the relationships between PA level and changes in anthropometric measures among university employees in a worksite wellness program. Methods. A registered dietitian provided individualized assessments at baseline followed by a 12-week education intervention with follow-up at 12 and 26 weeks. The International Physical Activity Questionnaire-Short Form was used to calculate PA ≤150 or ≥150 min/wk, median min/wk, and metabolic equivalent of task (MET) min/wk at each time point. Repeated-measures general linear model and nonparametric tests were used to assess significant differences over time. Results. Of the 64 participants, 89% were women and 50% were non-Hispanic white. At 12 and 26 weeks, participants experienced significant decreases in weight (P = .001). Among women, waist circumference and abdominal obesity decreased significantly (P < .01). PA ≥150 min/wk (n = 21) was associated with continued weight loss (P = .03) and decreases in body fat percentage (P = .02) between 12 and 26 weeks whereas PA ≤150 min/wk was associated with weight and body fat percentage regain during the same time period. Conclusion. Among women in a worksite wellness program, higher levels of PA were associated with avoiding weight and body fat regain following successful loss.

Clinical expression of facioscapulohumeral muscular dystrophy in carriers of 1–3 D4Z4 reduced alleles: experience of the FSHD Italian National Registry

ObjectivesFacioscapulohumeral muscular dystrophy type 1 (FSHD1) has been genetically linked to reduced numbers (≤8) of D4Z4 repeats at 4q35. Particularly severe FSHD cases, characterised by an infantile onset and presence...

Relationship between Microalbuminuria and Serum Vitamin D Levels in African Americans with Type 2 Diabetes

This cross sectional study examined the relationship between microalbuminuria (MA) and serum 25‐hydroxyvitamin D [25(OH)D] levels in African Americans with type 2 diabetes (T2D). Participants (n=129) were recruited from multiple sources from South Florida. MA was determined in urine samples by a semi‐quantitative assay (ImmunoDip, Diagnostic Chemicals Limited, Oxford, CT, US). Serum 25(OH)D levels were determined using a commercial ELISA kit from Immunodiagnostic Systems Limited (Scottsdale, AZ, US). Glycosylated hemoglobin (A1C) levels were measured from whole blood samples with the Roche Tina‐quant method. Statistical analysis included t‐test, chi‐square, General Linear Model (GLM) and Bonferroni post‐hoc test, controlling for age, gender, BMI, A1C and hypertension medications. MA was present in 40 (31%) of African Americans with T2D. There was a statistically significant difference in 25(OH)D levels between participants with and without MA (F(1,121) = 9.72, p = 0.002). Bonferroni post‐hoc test revealed that those with MA had significantly (p = 0.002) lower 25(OH)D levels (M = 39.5, SD = 13.8) as compared to those without MA (M = 51.5, SD = 23.4). Lower vitamin D levels might exacerbate kidney dysfunction in African Americans with T2D. Funding for this research was provided through an NIH/NIDDK sponsored grant.

A Racial/Ethnic Comparison of Teen Sexual Attitudes and Behavior

OBJECTIVES: The objective of this study was to compare and contrast sexual attitudes and behavior of white, African-American, Hispanic, Asian, Native American, Alaskan Native, Pacific Islander, Middle Eastern, and multi-racial/ethnic teens. METHODS: Participants were 99,085 teens in sexual abstinence programs across 16 states. One behavioral measure and 10 attitudinal measures were tested for differences using a univariate general linear model, ANOVAs, and Tukey's post-hoc tests. RESULTS: Statistically significant differences were found across the 9 racial/ethnic groups on most measures; Middle Eastern teens scored highest on abstinence attitudes and intentions whereas African-American teens scored lowest. CONCLUSIONS: Teen sexual attitudes and behavior can vary significantly by race/ethnicity and sex education programs may need to be more culturally sensitive. Language: en

Clinical Effects of Portulaca Oleracea Seeds on Dyslipidemia in Obese Adolescents: a Triple-blinded Randomized Controlled Trial

Objective:Childhood obesity is a major public health concern worldwide while the current epidemic may be secondary to over consumption of high-fat, energy-rich foods. Purslane (Portulaca oleracea L.) has been traditionally used in medicine for several antioxidant and anti-atherogenic activities. In this study the anti-dyslipidemic effects of P.oleracea was evaluated in obese adolescents.Methods:In this triple-blinded randomized placebo-controlled clinical trial which was done from July 2011 to June 2012, obese adolescent patients whom were referred to the Isfahan Cardiovascular Research Institute (Iran) were randomly allocated to the two arms of cases and controls. The cases group was asked to take one capsule containing powdered P. oleracea seeds (500 milligrams) two times a day for one month, and the controls group were asked to take identical but placebo (lactose) capsules in the same way. Biochemical parameters including 12-hours fasting serum levels of total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG) were measured before the initiation and after the completion of the study protocol.Findings:Total cholesterol, LDL-C, and TG showed statistically significant changes over time (one month) in the P. oleracea group (p < 0.05). However, between-group analysis using general linear model (multivariate) test revealed that the differences in the mentioned parameters between two study groups were statistically significant just for LDL-C and TG, while others did not differ significantly.Conclusion:P. oleracea L. may have positive effects on serum lipids profile which may be attributed to its polyphenolic and antioxidant compounds. This herbal drug seems to be well-tolerated in adolescent population as well. Further studies are recommended.

Blood Pressure and Dietary Related Risk Factors Associated with High Sodium Intake Assessed with 24-hour Urine Analysis for Korean Adults

Objectives: This study was conducted to examine blood pressure and other characteristics of a high sodium intake group assessed with 24-hr urine analysis and the dietary factors related to the risk of high sodium intake among Korean adults. Methods: A cross-sectional study was conducted with adults aged 20-59 years. Subjects who completed 24-hr urine collection (N = 205) were divided into 3 groups (tertile) according to the sodium intake estimated with 24-hour urine analysis. We compared the blood pressure, BMI and dietary related factors of the 3 groups (low, medium, high sodium intake group) with General Linear Model (GLM) and Duncan's multiple range test (p 14% (OR = 3.99; 95% CI: 1.404- 6.841). The dietary attitude related to increased risk of high sodium intake included 'enjoy dried fish and salted mackerel' (p < 0.001) and 'eat all broth of soup, stew or noodle' (p < 0.001). Conclusions: Because high sodium intake was associated with higher blood pressure, nutrition education should focus on alcohol consumption, emphasis on related dietary factors such as using low salt soybean paste, improvements in the habit of eating dried fish and salted mackerel or eating all broth of soup, stew or noodle. Korean J Community Nutr 19(6): 537~549, 2014

Are protected areas truly protected? The impact of road traffic on vertebrate fauna

The extension of road networks is considered one of the major factors affecting fauna survival. Roadkill has been documented widely and affects all taxonomic groups. Although roadkill is associated mainly with traffic density, some life-history traits of species and the area surrounding roads are expected to modify number of roadkills both taxonomically and geographically. Here we studied the number of roadkills of vertebrates in an extensive region in the northeastern Iberian Peninsula. We surveyed 820 km of 41 roads in two different seasons (spring and autumn), that differ in traffic intensity. In addition, we covered zones with distinct climatic characteristics and levels of protection of the surrounding habitats. Amphibians showed the highest number of roadkills whereas reptiles, birds and mammals had similar rates. General Linear Model tests showed no differences in roadkills by climatic region; however, differences in number of roadkills were linked to protection status, with the highest number of casualties in highly protected areas. Redundancy Analysis demonstrated that the number of amphibians and reptiles killed was associated with roads in highly protected areas whereas that of mammals and birds was linked to unprotected areas. Protected areas often receive many visitors, which in turn may increase wildlife casualties as a result of greater traffic density. We recommend that correction measures be taken to reduce the high number of vertebrate fauna killed along roads that cross protected areas.

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This study focuses on an initial construct validation of the new da Vinci Skills Simulator (Intuitive Surgical, Inc., Sunny vale, CA). We found that the overall score and time score correlated significantly with prior surgeon robotic experience. Subanalysis of all data collected did include comparison of all exercises. The analysis did not group the individual exercises into the arbitrary categories assigned by the manufacturer, including: EndoWrist® Manipulation, Camera and Clutching, Needle Control, Needle Driving, and Energy and Dissection. Because these categories were made arbitrarily, we felt it was more useful to look specifically at which of the exercises can be used to discern among the novice, intermediate, and expert surgeons. Our subanalysis did include looking at all exercises using the overall score and time to completion metrics comparing the 3 surgeon groups. Because of size limitations of the publication, the entire analysis was not included in the manuscript. A complete analysis of all exercises across the 3 groups is shown in Table 1. Table 1Ability of each exercise to distinguish between the 3 experience groups Exercise Name Score Time Novice vs Intermediate Intermediate vs Expert Novice vs Intermediate Intermediate vs Expert Camera targeting level I X Camera targeting level II X X Dots and needles level I X X Dots and needles level II X X Energy dissection level I X X Energy dissection level II X X X Energy switching X X Match board level I X X X Match board level II X X Match board level III X Needle targeting X X X Peg board level I X X Peg board level II X X Pick and Place Ring and rail level I X Ring and rail level II X X X Ring walk level I X X Ring walk level II X X X Ring walk level III X X Scaling Suture sponge level I X X Suture sponge level II X X Thread the rings X X X Tubes X X “X” signifies a significant value (P ≤.05) using the univariate general linear model test. Open table in a new tab “X” signifies a significant value (P ≤.05) using the univariate general linear model test. Editorial CommentUrologyVol. 80Issue 2PreviewThe combination of the console of the daVinci Surgical System (Intuitive Surgical, Inc., Sunny vale, CA) and MIMIC simulation technology (MIMIC Technologies, Seattle, WA) has been a long-awaited development and will positively impact robotic surgical training. Full-Text PDF

Nutritional status and food intake of patients with systemic psoriasis and psoriatic arthritis associated

To identify the nutritional status and food intake of individuals with systemic psoriasis and psoriatic arthritis associated. This is an exploratory and cross-sectional study with 34 men aged between 19 and 60 years seen at a Psoriasis Center. Participants were divided into systemic psoriasis group and arthritic-systemic psoriasis associated group. For nutritional assessment we used anthropometry, bioelectrical impedance analysis and whole-body plethysmography. Clinical and nutritional information were assessed using the clinical and nutritional history-taking, and the 24-hour dietary recall. For statistics the general linear model test (p < 0.05) was used. According to the body mass index 29.4% patients (n = 10) were eutrophic, 41.2% (n = 14) overweight and 29% (n = 10) obese. Almost all individuals (60%; n = 21) had body fat percentage above normal levels (> 25%) and a high risk for metabolic complications according to the waist circumference and the obesity index, however, there were no statistically significant differences between groups. The mean food intake, total fat, calories and protein were above recommended levels, being 58.8% for lipids (319.17 +/- 241.02 mg of cholesterol and 17.42 +/- 11.4 g saturated fatty acids); 29.4% for calories and 67.6% for proteins. Thus, regardless of the psoriasis type, an excessive consumption of calories, lipids, fatty acids, cholesterol and a higher incidence of overweight were found. The sample showed an abnormal nutritional condition, an increased risk for chronic diseases related to obesity, worsening of the psoriatic lesions, and poor quality of life.

Goodness-of-fit tests for general linear models with covariates missed at random

In this paper, we consider a model checking problem for general linear models with randomly missing covariates. Two types of score type tests with inverse probability weight, which is estimated by parameter and nonparameter methods respectively, are proposed to this goodness of fit problem. The asymptotic properties of the test statistics are developed under the null and local alternative hypothesis. Simulation study is carried out to present the performance of the sizes and powers of the tests. We illustrate the proposed method with a data set on monozygotic twins.

Impact of a four-year wellness programme on coronary artery disease risk in male employees

During the last few decades employers have realised that the health of an employee can have a positive influence on productivity.Thus, some corporate employers started implementing wellness programmes as part of their employee assistance programmes. In order to evaluate the impact of such programmes, the present study used a sample of 91 male employees. Baseline medical screening was performed after which a wellness programme was introduced. Employees were monitored every year for progress and the post-test was performed at the end of the four-year period. Employees were monitored for changes in total cholesterol (TC), high-density lipoprotein cholesterol (HDL), low- density lipoprotein cholesterol (LDL), triglycerides (TG), TC/HDL ratio, LDL/HDL ratio, fasting blood glucose (BG), systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI) and total coronary artery disease (CAD) risk.The Repeated Measures General Linear Model Test was used to determine significant changes (p&le;0.05) from pre-test to post-test. The results indicated that the wellness programme significantly decreased CAD risk by 25.6%. The TC, LDL-C, LDL/HDL-C ratio, TC/HDL-C ratio, BG, resting SBP and resting DBP also improved significantly, while TG showed a non-significant improvement. Two CAD risk factors however, deteriorated significantly namely,HDL and BMI.The major finding of this investigation suggests that a corporate wellness programme has long-term beneficial effects on CAD risk in men and that the reduction in CAD risk is mainly attributed to the beneficial effects of regular exercise and lifestyle modifications.Key words: Coronary artery disease, wellness, exercise, employee.

More Nutritious Food Is Served in Child-Care Homes Receiving Higher Federal Food Subsidies

The US Department of Agriculture's Child and Adult Care Food Program (CACFP) serves 2.3 million children by providing monetary subsidies for food to participating child-care providers. This cross-sectional study tested the hypothesis that higher reimbursement rates for food result in higher food expenditures and higher nutritional quality of foods served in family child-care homes participating in CACFP. Sixty family home child-care providers were recruited in 2008-2009 from King County, Washington. Half the sample received higher reimbursements and the other half received the lower rates. Participants provided a 5-day menu of meals/snacks served and food shopping receipts. The nutritional quality of foods served was assessed from portion-standardized menus. Nutritional quality was quantified as the mean adequacy (mean percent of dietary reference intake) for seven nutrients of concern for child health. Food expenditures were calculated by linking menus with receipts. Student's t tests for independent samples and general linear models were used to test for between-group differences. The two groups of providers were socioeconomically and demographically similar with comparable professional backgrounds. However, higher reimbursement providers had significantly greater menu expenditures than the lower reimbursement group ($2.36 vs $1.96/child/day; P=0.031). Reimbursement level was not associated with a difference in calories, but menus of higher reimbursement providers showed a significantly higher mean nutritional adequacy (64.5% vs 56.3%; P=0.033). The finding that reimbursement rates were positively associated with food expenditures and the nutritional quality of foods served suggests that raising CACFP reimbursements can improve child nutrition.

Effect of the contraction of medial rotators of the tibia on the electromyographic activity of vastus medialis and vastus lateralis

Purpose This study attempted to assess if the resisted contraction of medial rotators of the tibia increases the ratio between the activity of vastus medialis (VM) and vastus lateralis (VL) during maximal isometric contractions (MIC) of the quadriceps femoral (QF) muscle at 90° of knee flexion. Methods About 24 female subjects participated in this study, performing four series MIC of the QF. In the first series subjects performed only MIC of the QF muscle, whereas in the other three there was MIC of the QF with resisted contraction of medial rotators of the tibia, with the tibia positioned in medial, neutral and lateral rotation. During each contraction, VM and VL electromyographic signal (EMGs) and QF force were collected, being the EMGs root mean square (RMS) used to access the activity level of these muscles. Results The use of the General Linear Model (GLM) test showed that for α = 0.05 there was a significant increase in the VM:VL ratio when the resisted contraction of medial rotators of the tibia was performed with the tibia in medial ( p = <0.0001), neutral ( p = <0.0001) and lateral rotation ( p = 0.001). The same test showed that during MIC of the QF associated to resisted contraction of medial rotators of the tibia there were no significant differences in the VM:VL ratio between the three tibial rotation positions adopted ( p = 0.866 [medial–neutral]; p = 0.106 [medial–lateral]; p = 0.068 [neutral–lateral]). Conclusions The resisted contraction of medial rotators of the tibia increases the VM:VL ratio during MIC of the QF and the tibial rotation position does not influence the VM:VL ratio during MIC associated to resisted contraction of medial rotators of the tibia.

Tests for multiple regression based on simplicial depth

A general approach for developing distribution free tests for general linear models based on simplicial depth is applied to multiple regression. The tests are based on the asymptotic distribution of the simplicial regression depth, which depends only on the distribution law of the vector product of regressor variables. Based on this formula, the spectral decomposition and thus the asymptotic distribution is derived for multiple regression through the origin and multiple regression with Cauchy distributed explanatory variables. The errors may be heteroscedastic and the concrete form of the error distribution does not need to be known. Moreover, the asymptotic distribution for multiple regression with intercept does not depend on the location and scale of the explanatory variables. A simulation study suggests that the tests can be applied also to normal distributed explanatory variables. An application on multiple regression for shape analysis of fishes demonstrates the applicability of the new tests and in particular their outlier robustness.

The Effect of Yoga Postures on Balance, Flexibility, and Strength in Healthy High School Females

Objective: The purpose of this study was to document the effects of yoga interventions on balance, flexibility, and strength in adolescent girls 14 to 18 years. Study Design: Quasi-experimental, nonrandomized. Background: Research on the effects of yoga on balance, flexibility, and strength has focused on adults, although yoga is being marketed to all ages. Methods and Measures: A convenience sample of 33 female adolescents participated in yoga training 2 times per week and a walking program 3 times per week, for 7 weeks. The instructor-led group received instruction from a registered yoga therapist in person, while the video-led group watched a tape of the instructor-led session. Pre- and postmeasurements of weight, hamstring flexibility, body fat, strength, and balance were collected. Means were computed for all variables. Levene’s tests for equality of variances were run to determine baseline homogeneity. Histograms with a normal curve superimposed were drawn to check for normal distribution. Repeated-measures general linear model tests were run to test for both within- and betweensubjects factors, as well as interactions between the two. Results: Data were normally distributed and groups were not significantly different at baseline (P .05). There was a statistically significant within-subject difference (pretest to posttest) for range-of-motion right (P .034) and rangeof-motion left (P .036) as measured by the 90/90 hamstring flexibility test. There were no statistically significant differences between the instructor- and video-led groups for any of the measured variables. Conclusions: Yoga may be a useful adjunct to therapy programs and provide a method to keep this age group interested in exercise.

Factors affecting the shear bond strength of metal and ceramic brackets bonded to different ceramic surfaces

The aims of this study were to evaluate the shear bond strength (SBS) of metal and ceramic brackets bonded to two different all-ceramic crowns, IPS Empress 2 and In-Ceram Alumina, to compare the SBS between hydrofluoric acid (HFA), phosphoric acid etched, and sandblasted, non-etched all-ceramic surfaces. Ninety-six all-ceramic crowns were fabricated resembling a maxillary left first premolar. The crowns were divided into eight groups: (1) metal brackets bonded to sandblasted 9.6 per cent HFA-etched IPS Empress 2 crowns; (2) metal brackets bonded to sandblasted 9.6 per cent HFA-etched In-Ceram crowns; (3) ceramic brackets bonded to sandblasted 9.6 per cent HFA-etched IPS Empress 2 crowns; (4) ceramic brackets bonded to sandblasted 9.6 per cent HFA-etched In-Ceram crowns; (5) metal brackets bonded to sandblasted 37 per cent phosphoric acid-etched IPS Empress 2 crowns; (6) metal brackets bonded to sandblasted 37 per cent phosphoric acid-etched In-Ceram crowns; (7) metal brackets bonded to sandblasted, non-etched IPS Empress 2 crowns; and (8) metal brackets bonded to sandblasted, non-etched In-Ceram crowns. Metal and ceramic orthodontic brackets were bonded using a conventional light polymerizing adhesive resin. An Instron universal testing machine was used to determine the SBS at a crosshead speed of 0.1 mm/minute. Comparison between groups was performed using a univariate general linear model and chi-squared tests. The highest mean SBS was found in group 3 (120.15 +/- 45.05 N) and the lowest in group 8 (57.86 +/- 26.20 N). Of all the variables studied, surface treatment was the only factor that significantly affected SBS (P < 0.001). Acid etch application to sandblasted surfaces significantly increased the SBS in groups 1, 2, 5, and 6. The SBS of metal brackets debonded from groups 1, 3, and 5 were not significantly different from those of groups 2, 4, and 6. All debonded metal brackets revealed a similar pattern of bond failure at the adhesive-restorative interface. However, ceramic brackets had a significantly different adhesive failure pattern with dominant failure at the adhesive-bracket interface. Ceramic fractures after bracket removal were found more often in groups 1-4. No significant difference in ceramic fracture was observed between the IPS Empress 2 and In-Ceram groups.

The effects of an anabolic agent on body composition and pulmonary function in tetraplegia: a pilot study

Prospective repeated-measures longitudinal study. To determine if an 8-week course of an oral anabolic steroid can positively effect body composition or pulmonary function in healthy individuals with chronic tetraplegia. United States. Oxandrolone (20 mg per day) was administered for 8 weeks to 10 men with motor complete tetraplegia. Dual X-ray absorptiometry scans, pulmonary function tests (PFTs), serum lipids and liver function tests (LFTs) were obtained at baseline, 4, 8, 12 and 20 weeks. To analyze change over time, a repeated measures General Linear Model and nonparametric tests were utilized. Following treatment, total lean body mass (LBM) increased 1.9% and LBM of the arms increased 5.4%. Total body fat decreased 1.5%, and increased 3.9% in the arms and, on average, combined measures of PFTs improved 2.2%. High-density lipoprotein cholesterol decreased 31.8%, low density lipoprotein cholesterol increased 41.2%, and LFTs increased 9.7-65.6% while on therapy but all trended to baseline at 20 weeks. Baseline body composition was characterized by a high proportion of fat and a body mass index that underestimated chronic disease risk. Treatment with oxandrolone was associated with modest improvements in PFTs and in arm and total body LBM. Unfavorable changes in serum lipids and LFTs indicate that reported benefits of using oxandrolone in this population must be carefully weighed against potential adverse effects.

Likelihood-Based Hypothesis Tests for Brain Activation Detection From MRI Data Disturbed by Colored Noise: A Simulation Study

Functional magnetic resonance imaging (fMRI) data that are corrupted by temporally colored noise are generally preprocessed (i.e., prewhitened or precolored) prior to functional activation detection. In this paper, we propose likelihood-based hypothesis tests that account for colored noise directly within the framework of functional activation detection. Three likelihood-based tests are proposed: the generalized likelihood ratio (GLR) test, the Wald test, and the Rao test. The fMRI time series is modeled as a linear regression model, where one regressor describes the task-related hemodynamic response, one regressor accounts for a constant baseline and one regressor describes potential drift. The temporal correlation structure of the noise is modeled as an autoregressive (AR) model. The order of the AR model is determined from practical null data sets using Akaike's information criterion (with penalty factor 3) as order selection criterion. The tests proposed are based on exact expressions for the likelihood function of the data. Using Monte Carlo simulation experiments, the performance of the proposed tests is evaluated in terms of detection rate and false alarm rate properties and compared to the current general linear model (GLM) test, which estimates the coloring of the noise in a separate step. Results show that theoretical asymptotic distributions of the GLM, GLR, and Wald test statistics cannot be reliably used for computing thresholds for activation detection from finite length time series. Furthermore, it is shown that, for a fixed false alarm rate, the detection rate of the proposed GLR test statistic is slightly, but (statistically) significantly improved compared to that of the common GLM-based tests. Finally, simulations results reveal that all tests considered show seriously inferior performance if the order of the AR model is not chosen sufficiently high to give an adequate description of the correlation structure of the noise, whereas the effects of (slightly) overmodeling are observed to be less harmful.