In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

[EX Q]: Context: Recent work has identified deficits in dual-task gait balance control for up to 2 months after adolescent concussion; however, how resumption of preinjury physical activities affects recovery is unknown.', 'The objective of this study is to examine how return to activity (RTA) affects recovery from concussion on measures of symptom severity, cognition, and balance control during single-task and dual-task walking.', 'Nineteen adolescents with concussion who returned to preinjury activity within 2 months after injury and 19 uninjured, matched controls completed symptom inventories, computerized cognitive testing, and single-task and dual-task gait analyses. Concussion participants were assessed at five time points: within 72 h, 1 wk, 2 wk, 1 month, and 2 months postinjury. Control participants were assessed at the same time points as their matched concussion counterparts. RTA day was documented as the postinjury day in which physical activity participation was allowed. The effect of returning to physical activity was assessed by examining the percent change on each dependent variable across time before and directly after the RTA. Data were analyzed by two-way mixed effects ANOVAs.', 'After the RTA day, concussion participants significantly increased their total center-of-mass medial/lateral displacement (P = 0.009, ηp = .175) and peak velocity (P = 0.048, ηp = 0.104) during dual-task walking when compared with pre-RTA data, whereas no changes for the concussion group or between groups were detected on measures of single-task walking, forward movement, or cognition.\Question: Does return to activity after concussion affect dual-task gait balance control recovery?
[EX A]: Adolescents with concussion displayed increased center-of-mass medial/lateral displacement and velocity during dual-task walking after RTA, suggesting a regression of recovery in gait balance control. This study reinforces the need for a multifaceted approach to concussion management and continued monitoring beyond the point of clinical recovery.

[EX Q]: Context: The incidence and predictors of spontaneous hepatitis B surface-antigen (HBsAg) seroclearance in patients with chronic hepatitis B virus (HBV) were evaluated.', 'A total of 1427 patients with chronic HBV infection, who were followed between 1994 and 2013, were investigated in this retrospective study. All data were extracted from patient files.', 'Spontaneous HBsAg seroclearance occurred in 84 patients during 8798 person-years of follow-up. The patients were categorized into 3 groups at follow-up based on HBV DNA features as continuously <100 copies/mL (Group A), 0-10,000 copies/mL (Group B), and 0 to >10,000 copies/mL (Group C). Alanine aminotransferase features in the 2 groups were categorized as continuously normal (<40 U/L) and 0 to >40 U/L. Spontaneous HBsAg seroclearance was seen primarily in patients with Group A HBV DNA features, and continuously low HBV DNA values were the main predictor of HBsAg seroclearance (P < 0.001).\Question: Is a persistently low HBV DNA level a predictor of spontaneous HBsAg clearance in patients with chronic hepatitis B?
[EX A]: These results suggest that a continuously low viral load is the most important factor affecting spontaneous HBsAg seroclearance.

[EX Q]: Context: This study compared the pharmacokinetics of a single dose of 1% testosterone solution after application to the inner arm or the axilla as application sites for transdermal testosterone therapy.', 'Healthy, not pregnant, premenopausal women, 18 to 45 years of age with a body mass index of 20 to 28 kg/m(2) were enrolled into a single-center, open-label, randomized, 2-way crossover study. Serum total testosterone (TT), free testosterone (fT), and sex hormone binding globulin concentrations were measured. Pharmacokinetic parameters determined from serum TT and fT included area under the serum concentration versus time curve from time zero (pre-dose) until 72 hours post-dose (AUC0-72), Cmax, and Tmax. Descriptive statistics were performed on serum concentrations of TT and fT for each site. ANOVA was performed on AUC0-72 and Cmax.', 'A single-dose application of 1% testosterone solution to the inner arm and the axilla produced clear increases in TT and fT. Slower and lower increases in TT and fT were observed after treatment to the inner arm. Based on baseline-corrected AUC versus time curves, the bioavailability of 1% testosterone solution was increased 2-fold for the axilla compared with the inner arm.\Question: Does application site affect the pharmacokinetics of topical testosterone applied to the axilla compared with the inner arm?
[EX A]:
The absorption of a 1% testosterone solution was significantly greater after application to the axilla than to the inner arm. Study number DDS16; Australian Therapeutic Goods Administration, CTN 2005/158.