scholarly journals Effectiveness of Physical Activity Intervention on ADHD Symptoms: A Systematic Review and Meta-Analysis

2021 ◽  
Vol 12 ◽  
Author(s):  
Yongtao Xie ◽  
Xuping Gao ◽  
Yiling Song ◽  
Xiaotong Zhu ◽  
Mengge Chen ◽  
...  
Keyword(s):  
Physical Activity ◽  
Sample Size ◽  
Motor Skills ◽  
Randomized Clinical Trials ◽  
Meta Analysis ◽  
Attention Problems ◽  
Cochrane Library ◽  
Large Sample Size ◽  
Group Control ◽  
Meta Analyses

Objective: To assess the effectiveness of physical activity (PA) intervention on attention-deficit/hyperactivity disorder (ADHD)-related symptoms.Method: Studies that investigated PA intervention for ADHD-related symptoms were identified through searching PubMed, Web of Science, Cochrane Library, and Embase databases from inception through June 2021. Standardized mean difference (SMD) with 95% confidence interval (CI) was used to assess the effectiveness of PA intervention on improving ADHD-related symptoms. The meta-analyses were conducted using fixed-effect or random-effect models according to the heterogeneity of the studies.Results: Nine before–after studies (232 participants) and 14 two-group control studies (162 participants/141 controls) were included in this meta-analysis. Combined results for before–after studies indicated significant improvements on all studied ADHD-related symptoms (inattention: SMD = 0.604, 95% CI: 0.374–0.834, p < 0.001; hyperactivity/impulsivity: SMD = 0.676, 95% CI: 0.401–0.950, p < 0.001; emotional problems: SMD = 0.416, 95% CI: 0.283–0.549, p < 0.001; behavioral problems: SMD = 0.347, 95% CI: 0.202–0.492, p < 0.001). Meta-analyses for two-group control studies further confirmed that PA intervention significantly improved the inattentive symptom (SMD = 0.715, 95% CI: 0.105, 1.325, p = 0.022). Subgroup analyses suggested significant beneficial effect on inattention symptoms in children. Moreover, closed motor skills were beneficial for hyperactive/impulsive problems (SMD = 0.671, p < 0.001), while open motor skills were beneficial for attention problems (SMD = 0.455, p = 0.049). When excluding studies with combined medication, the studies in unmedicated participants in before–after studies still showed significant results in all studied ADHD-related symptoms as in the overall analysis. Given the limited sample size, the best frequency and intensity of PA intervention need further investigation.Conclusion: Our results suggested that PA intervention could possibly improve ADHD-related symptoms, especially inattention symptoms. Closed-skill and open-skill activities could be beneficial for hyperactivity/impulsivity and inattention symptoms, respectively. Further high-quality randomized clinical trials with large sample size are needed.

Laser Influence on Dental Sensitivity Compared to Other Light Sources Used During In-office Dental Bleaching: Systematic Review and Meta-analysis

2020 ◽  
Vol 45 (6) ◽  
pp. 589-597
Author(s):  
BGS Casado ◽  
EP Pellizzer ◽  
JR Souto Maior ◽  
CAA Lemos ◽  
BCE Vasconcelos ◽  
...  
Keyword(s):  
Randomized Clinical Trials ◽  
Color Change ◽  
Meta Analysis ◽  
Present Review ◽  
Cochrane Library ◽  
Light Sources ◽  
Eligibility Criteria ◽  
Tooth Color ◽  
Significant Difference ◽  
Meta Analyses

Clinical Relevance The use of laser light during bleaching will not reduce the incidence or severity of sensitivity and will not increase the degree of color change compared with nonlaser light sources. SUMMARY Objective: To evaluate whether the use of laser during in-office bleaching promotes a reduction in dental sensitivity after bleaching compared with other light sources. Methods: The present review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and is registered with PROSPERO (CDR42018096591). Searches were conducted in the PubMed/Medline, Web of Science, and Cochrane Library databases for relevant articles published up to August 2018. Only randomized clinical trials among adults that compared the use of laser during in-office whitening and other light sources were considered eligible. Results: After analysis of the texts retrieved during the database search, six articles met the eligibility criteria and were selected for the present review. For the outcome dental sensitivity, no significant difference was found favoring any type of light either for intensity (mean difference [MD]: −1.60; confidence interval [CI]: −3.42 to 0.22; p=0.09) or incidence (MD: 1.00; CI: 0.755 to 1.33; p=1.00). Regarding change in tooth color, no significant differences were found between the use of the laser and other light sources (MD: −2.22; CI: −6.36 to 1.93; p=0.29). Conclusions: Within the limitations of the present study, laser exerts no influence on tooth sensitivity compared with other light sources when used during in-office bleaching. The included studies demonstrated that laser use during in-office bleaching may have no influence on tooth color change.

scholarly journals The Optimal Time of Applying Enteral Immunonutrition in Esophageal Cancer Patients Receiving Esophagectomy: A Network Meta-Analysis of Randomized Clinical Trials

2021 ◽  
Author(s):  
Xu Tian ◽  
Yan-Fei Jin ◽  
Zhao-Li Zhang ◽  
Hui Chen ◽  
Wei-Qing Chen ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Cancer Patients ◽  
Randomized Clinical Trials ◽  
Meta Analysis ◽  
Infectious Complications ◽  
Cochrane Library ◽  
Optimal Time ◽  
Registration Number ◽  
Meta Analyses ◽  
The Impact

Abstract Background: Enteral immunonutrition (EIN) has been extensively applied in cancer patients, however its role in esophageal cancer (EC) patients receiving esophagectomy remains unclear. We performed this network meta-analysis to investigate the impact of EIN on patients undergoing surgery for EC and further determine the optimal time of applying EIN.Methods: We searched PubMed, EMBASE, Cochrane library, and China National Knowledgement Infrastructure (CNKI) to identify eligible studies. Categorical data was expressed as the odds ratio with 95% confidence interval (CI), and continuous data was expressed as mean difference (MD) with 95% CI. Pair-wise and network meta-analysis was performed to evaluate the impact of EIN on clinical outcomes using RevMan 5.3 and ADDIS V.1.16.8 softwares. The surface under the cumulative ranking curve (SUCRA) was calculated to rank all nutritional regimes.Results: Total 14 studies involving 1071 patients were included. Pair-wise meta-analysis indicated no difference between EIN regardless of the application time and standard EN (SEN), however subgroup analyses found that postoperative EIN was associated with decreased incidence of total infectious complications (OR=0.47; 95%CI=0.26 to 0.84; p=0.01) and pneumonia (OR=0.47; 95%CI=0.25 to 0.90; p=0.02) and shortened LOH (MD=-1.01; 95%CI=-1.44 to -0.57; p<0.001) compared to SEN, which were all supported by network meta-analyses. Ranking probability analysis further indicated that postoperative EIN has the highest probability of being the optimal option in terms of these three outcomes.Conclusions: Postoperative EIN should be preferentially utilized in EC patients undergoing esophagectomy because it has optimal potential of decreasing the risk of total infectious complications and pneumonia and shortening LOH.OSF registration number: 10.17605/OSF.IO/KJ9UY.

scholarly journals Comparing the Effects of Docosahexaenoic and Eicosapentaenoic Acids on Inflammation Markers Using Pairwise and Network Meta-Analyses of Randomized Controlled Trials

2020 ◽  
Author(s):  
Cécile Vors ◽  
Janie Allaire ◽  
Sonia Blanco Mejia ◽  
Tauseef A Khan ◽  
John L Sievenpiper ◽  
...  
Keyword(s):  
Randomized Clinical Trials ◽  
Meta Analysis ◽  
Cochrane Library ◽  
Eligibility Criteria ◽  
Necrosis Factor Alpha ◽  
Assessment Development ◽  
Evaluation Approach ◽  
Tnf Α ◽  
Mean Differences ◽  
Meta Analyses

ABSTRACT Recent data from randomized clinical trials (RCTs) suggest that DHA may have stronger anti-inflammatory effects than EPA. This body of evidence has not yet been quantitatively reviewed. The aim of this study was to compare the effect of DHA and EPA on several markers of systemic inflammation by pairwise and network meta-analyses of RCTs. MEDLINE, EMBASE, and The Cochrane Library were searched through to September 2019. We included RCTs of ≥7 d on adults regardless of health status that directly compared the effects of DHA with EPA and RCTs of indirect comparisons, in which the effects of DHA or EPA were compared individually to a control fatty acid. Differences in circulating concentrations of C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and adiponectin were the primary outcome measures. Data were pooled by pairwise and network meta-analysis and expressed as mean differences (MDs) with 95% CIs. Heterogeneity was assessed (Cochran Q statistic) and quantified (I2 statistic) in the pairwise meta-analysis. Inconsistency and transitivity were evaluated in the network meta-analysis. The certainty of evidence was assessed using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach. Eligibility criteria were met by 5 RCTs (N = 411) for the pairwise meta-analysis and 20 RCTs (N = 1231) for the network meta-analysis. In the pairwise meta-analysis, DHA and EPA had similar effects on plasma CRP [MDDHA versus EPA = 0.14 mg/L (95% CI: –0.57, 0.85); I2 = 61%], IL-6 [MDDHA versus EPA = 0.10 pg/mL (–0.15, 0.34); I2 = 40%], and TNF-α [MDDHA versus EPA = –0.10 pg/mL (–0.37, 0.18); I2 = 40%]. In the network meta-analysis, the effects of DHA and EPA on plasma CRP [MDDHA versus EPA = –0.33 mg/L (–0.75, 0.10)], IL-6 [MDDHA versus EPA = 0.09 pg/mL (–0.12, 0.30)], and TNF-α [MDDHA versus EPA = –0.02 pg/mL (–0.25, 0.20)] were also similar. DHA and EPA had similar effects on plasma adiponectin in the network meta-analysis. Results from pairwise and network meta-analyses suggest that supplementation with either DHA or EPA does not differentially modify systemic markers of subclinical inflammation.

scholarly journals Effectiveness of adult community-based physical activity interventions with objective physical activity measurements and long-term follow-up: a systematic review and meta-analysis

BMJ Open ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. e034541
Author(s):  
Charlotte Wahlich ◽  
Umar A R Chaudhry ◽  
Rebecca Fortescue ◽  
Derek G Cook ◽  
Shashivadan Hirani ◽  
...  
Keyword(s):  
Physical Activity ◽  
Systematic Review ◽  
Meta Analysis ◽  
Risk Of Bias ◽  
Cochrane Library ◽  
Community Based ◽  
Intervention Effects ◽  
Meta Analyses

ObjectiveTo identify randomised controlled trials (RCTs) of physical activity (PA) interventions with objective PA outcomes in adults and to evaluate whether intervention effects were sustained beyond 12 months.DesignSystematic review and meta-analysis.Data sourcesSeven databases (Medline, Embase, PsycINFO, Web of Science, Cochrane library, CINAHL (Cumulative Index of Nursing and Allied Health Literature) and ASSIA (Applied Social Sciences Index and Abstracts)) were searched from January 2000 until December 2019.Eligibility criteriaRCTs reporting objective PA outcomes beyond 12 months with community-based participants aged ≥18 years were included; those where controls received active interventions, including advice to increase PA levels, were excluded.Data extraction and synthesisTwo independent reviewers completed extraction of aggregate data and assessed risk of bias. Meta-analyses used random-effects models at different follow-up points. Primary outcomes were daily steps and weekly minutes of moderate-to-vigorous PA (MVPA).ResultsOf 33 282 records identified, nine studies (at generally low risk of bias) were included, five in meta-analyses with 12 months to 4 year follow-up. We observed 12 month increases for intervention vs control participants in steps/day (mean difference (MD)=554 (95% CIs: 384 to 724) p<0.0001, I2=0%; 2446 participants; four studies) and weekly MVPA minutes (MD=35 (95% CI: 27 to 43) p<0.0001, I2=0%; 2647 participants; four studies). Effects were sustained up to 4 years for steps/day (MD=494 (95% CI: 251 to 738) p<0.0001, I2=0%; 1944 participants; four studies) and weekly MVPA minutes (MD=25 (95% CI: 13 to 37) p<0.0001, I2=0%; 1458 participants; three studies).ConclusionsThere are few PA interventions with objective follow-up beyond 12 months, more studies are needed. However, this review provided evidence of PA intervention effects beyond 12 months and sustained up to 4 years for both steps/day and MVPA. These findings have important implications for potential long-term health benefits.PROSPERO registration numberCRD42017075753.

scholarly journals Efficacy and safety of paranasal sinus balloon catheter dilation in pediatric chronic rhinosinusitis: a systematic review

2020 ◽  
Vol 49 (1) ◽  
Author(s):  
Ahmad A. Mirza ◽  
Hatim Y. Shawli ◽  
Talal A. Alandejani ◽  
Sattam M. Aljuaid ◽  
Mahmoud Alreefi ◽  
...  
Keyword(s):  
Side Effects ◽  
Sample Size ◽  
Chronic Rhinosinusitis ◽  
Pediatric Patients ◽  
Meta Analysis ◽  
Balloon Catheter ◽  
Cochrane Library ◽  
Large Sample Size ◽  
Randomized Controlled Studies

Abstract Objective Chronic rhinosinusitis (CRS) negatively affects quality of life (QoL), and balloon catheter sinuplasty (BCS) has shown good outcomes in adult patients. However, there has not been much research on the effects of BCS on pediatric patients. The objective of this review is to systematically assess the literature for studies demonstrating the effectiveness and safety of BCS in pediatric CRS patients. Data sources PubMed, Embase and Cochrane Library. Study selection We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis recommendations (PRISMA) to conduct our study. Observational- and interventional-based studies reporting efficacy and/or side effects of BCS among pediatric populations were included. Efficacy was evaluated by clinically reliable measures including Sino-Nasal 5 (SN-5) QoL scale. Antibiotic usage and revision surgery were also evaluated. Data extraction Articles were screened, and data were obtained. Study design, sample size and demographics, treated sinuses, criteria of inclusion, adjunct procedure(s), follow-up time, and outcomes measured were reported. Main findings Out of 112 articles identified, 10 articles were included: two interventional controlled trials and eight observational studies. All studies evaluating QoL by SN-5 showed a remarkable reduction in SN-5 score postoperatively. Improvement in the computed tomography (CT) and endoscopic findings for up to 1 year after operation was reported. Furthermore, the majority of patinets treated with BCS did not recieve any course of sinusitis-indicated antibiotics during long-term follow-up, and they had low surgical revision rates. Minor side effects were reported, most commonly synechia. Conclusion Available evidence suggests that BCS is safe and effective for the treatment of CRS in pediatric patients. Future randomized controlled studies with large sample size are warranted. Such studies can further determine the efficacy of BCS in managing children with CRS.

Physical Activity Interventions in Faith-Based Organizations: A Systematic Review

2017 ◽  
Vol 32 (3) ◽  
pp. 677-690 ◽  
Author(s):  
Maíra Tristão Parra ◽  
Gustavo J. M. Porfírio ◽  
Elva M. Arredondo ◽  
Álvaro N. Atallah
Keyword(s):  
Physical Activity ◽  
Randomized Clinical Trials ◽  
Data Extraction ◽  
The United States ◽  
Cochrane Library ◽  
Publication Date ◽  
Faith Based ◽  
Physical Activity Interventions ◽  
Faith Based Organizations ◽  
Meta Analyses

Objective: To review and assess the effectiveness of physical activity interventions delivered in faith-based organizations. Data Source: We searched the Cochrane Library, DoPHER, EMBASE, LILACS, MEDLINE, PsycINFO, WHO ICTRP, and Clinicaltrials.gov databases until January 2016, without restriction of language or publication date. Study Inclusion and Exclusion Criteria: Randomized and nonrandomized controlled trials investigating physical activity interventions for adults delivered in faith-based organizations. Data Extraction: Two independent reviewers extracted data and assessed study methodological quality. Data Synthesis: We used relative risk and mean difference with 95% confidence interval to estimate the effect of the interventions on measures of physical activity, physical fitness, and health. Results: The review included 18 studies. Study participants were predominantly female, and the majority of trials were conducted in the United States. Study heterogeneity did not allow us to conduct meta-analyses. Although interventions delivered in faith-based organizations increased physical activity and positively influenced measures of health and fitness in participants, the quality of the evidence was very low. Conclusion: Faith-based organizations are promising settings to promote physical activity, consequently addressing health disparities. However, high-quality randomized clinical trials are needed to adequately assess the effectiveness of interventions delivered in faith-based organizations.

scholarly journals Effect of leisure-time physical activity in controlling hypertension: a systematic review and meta-analysis protocol

BMJ Open ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. e056270
Author(s):  
Md Shariful Islam ◽  
Md Golam Rabbani ◽  
Ammatul Fardousi ◽  
Monaemul Islam Sizear ◽  
KM Saif-Ur-Rahman
Keyword(s):  
Physical Activity ◽  
Blood Pressure ◽  
Leisure Time ◽  
Leisure Time Physical Activity ◽  
Data Extraction ◽  
Meta Analysis ◽  
Cochrane Library ◽  
Ethical Approval ◽  
Registration Number ◽  
Meta Analyses

IntroductionHypertension is a major risk factor for cardiovascular diseases. In 2015, over 1.13 billion individuals worldwide had hypertension. Globally, it results in 10.8 million deaths every year. Around half of the individuals do not continue treatment with medicine to control blood pressure. Physical activity, a non-pharmacological option of treatment, reduces blood pressure. We aim in this research to examine the effect of leisure-time physical activity in controlling blood pressure.Methods and analysisWe will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses to conduct this study. We will perform a systematic search in Medline/PubMed, Embase, Scopus, Web of Science, Physical Education Index (ProQuest) and CENTRAL (the Cochrane Library). Both experimental and observational studies will be included. The study population would be people with hypertension. Two reviewers will perform screening of the articles, bias assessment and data extraction independently. We will use the Joanna Briggs Institute Critical Appraisal Tools to assess the risk of bias. We will conduct a meta-analysis if it is applicable.Ethics and disseminationThe results will be published in peer-reviewed journals and presented at relevant scientific seminars and conferences. Ethical approval is not applicable.PROSPERO registration numberCRD42021260751.

scholarly journals Representation of Women in Randomized Trials in Cardiac Surgery: A Meta‐Analysis

2021 ◽  
Author(s):  
Mario Gaudino ◽  
Michele Di Mauro ◽  
Stephen E. Fremes ◽  
Antonino Di Franco
Keyword(s):  
Cardiac Surgery ◽  
Sample Size ◽  
Randomized Clinical Trials ◽  
Meta Analysis ◽  
Geographic Location ◽  
Coronary Bypass ◽  
Cardiac Surgical Procedures ◽  
Systematic Evaluation ◽  
Cochrane Library ◽  
Representation Of Women

Background Women have traditionally been underrepresented in randomized clinical trials (RCTs). We performed a systematic evaluation of the inclusion of women in cardiac surgery RCTs published in the past 2 decades. Methods and Results MEDLINE, EMBASE, and the Cochrane Library were searched (2000 to July 2020) for RCTs written in English, comparing ≥2 adult cardiac surgical procedures. The percentage of women enrolled and its association with year of publication, sample size, mean age, funding source, geographic location, number of sites involved, and interventions tested were analyzed using a meta‐analytic approach. Fifty‐one trials were included. Of 25 425 total patients, 5029 were women (20.8%; 95% CI, 17.6–24.4; range, 0.5%–57.9%). The proportion of women dropped significantly during the study period (29.6% in 2000 versus 13.1% in 2019, P <0.001). Women were significantly more represented in European trials (26.2%; 95% CI, 21.2–31.9), and less represented in trials of coronary bypass surgery versus other interventions (16.8%; 95% CI, 12.3–22.7 versus 33.6%; 95% CI, 27.4–40.5; P =0.0002) and in trials enrolling younger patients ( P =0.009); the percentage of women was higher in industry‐sponsored versus non‐industry sponsored trials (31.7%; 95% CI, 27.2–36.6 versus 15.5%; 95% CI, 10.0–23.2; P =0.0004) and was not associated with trial sample size ( P =0.52) or study design (multicenter versus monocenter: P =0.22). After exclusion of trials conducted at Veteran Affairs centers, women representation was 24.4% (95% CI, 21.1–28.0; range, 10.4%–57.9%), with no significant changes during the study period. Conclusions The proportion of women in cardiac surgery trials is low and likely inadequate to provide meaningful estimates of the treatment effect.

scholarly journals Corticosteroids Treatment for Patients With Coronavirus Disease-2019 (COVID-19) With Different Disease Severity: a Systematic Review and Meta-analysis Protocol

2021 ◽  
Author(s):  
Shaofei Lou ◽  
Kaizhuang Huang ◽  
Jiao Jiang ◽  
Ningjun Li
Keyword(s):  
Systematic Review ◽  
Disease Severity ◽  
Oxygen Therapy ◽  
Randomized Clinical Trials ◽  
Meta Analysis ◽  
Antiviral Agents ◽  
Adverse Outcomes ◽  
Cochrane Library ◽  
Registration Number ◽  
Meta Analyses

Abstract Introduction: As the coronavirus disease 2019 (COVID-19) pandemic progresses, identifying effective antiviral agents to treat the COVID-19 is of most urgency. Efficacy and safety of corticosteroids in patients with COVID-19 still are debated. Because high-quality randomized clinical trials (RCTs) on the use of corticosteroids for patients with COVID-19 recently were published recently, we aim to conduct a systematic review and meta-analysis of RCTs on corticosteroids therapy in patients with different disease severity to ascertain the effect on survival. Methods: We will undertake a comprehensive literature search among PubMed, EMBASE, Cochrane Library, medRxiv, and bioRxiv from their inception onwards to identify relevant RCTs. Two reviewers will independently extract data and conduct risk of bias assessments. The primary outcome is all-cause mortality, mortality of mechanically ventilated patients and patients who did not receive oxygen therapy. Secondary outcomes include need for mechanical ventilation or oxygen therapy and incidence of adverse outcomes. Heterogeneity of the estimates across studies will be assessed. Outcomes will be analyzed to pooled risk ratio and pertinent 95% confidence interval. A subgroup analysis will be conducted by disease severity to explore the source of heterogeneity. The systematic review and meta-analysis will be presented according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses. Discussion: This systematic review will provide an overview of the current state of evidence concerning the effect of corticosteroids on survival of patients with COVID-19 depended on the disease severity. Also, this systematic review will show the limitations and strengths of the studies available in the literature, as well as recommendations for future avenues of research will be given. PROSPERO registration number: CRD42020227740.

scholarly journals Depression and Objectively Measured Physical Activity: A Systematic Review and Meta-Analysis

2020 ◽  
Vol 17 (10) ◽  
pp. 3738 ◽  
Author(s):  
Vincenza Gianfredi ◽  
Lorenzo Blandi ◽  
Stefano Cacitti ◽  
Mirko Minelli ◽  
Carlo Signorelli ◽  
...  
Keyword(s):  
Physical Activity ◽  
Systematic Review ◽  
Meta Analysis ◽  
Cochrane Collaboration ◽  
Protective Role ◽  
Cochrane Library ◽  
P Value ◽  
Meta Analyses ◽  
The Cochrane Collaboration ◽  
Objectively Measured

Depression is a major contributor to the overall global burden of disease, with high prevalence and relapse rate. Several factors have been considered in order to reduce the depression burden. Among them, physical activity (PA) showed a potential protective role. However, evidence is contrasting probably because of the differences in PA measurement. The aim of this systematic review with meta-analysis is to assess the association between objectively measured PA and incident and prevalent depression. The systematic review was conducted according to methods recommended by the Cochrane Collaboration and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Relevant papers published through 31 August 2019 were identified searching through the electronic databases PubMed/MEDLINE, Excerpta Medica dataBASE (Embase), PsycINFO, Scopus, Web of Science (WoS), and the Cochrane Library. All analyses were conducted using ProMeta3. Finally, 42 studies met inclusion criteria. The overall Effect size (ES) of depression for the highest vs. the lowest level of PA was −1.16 [(95% CI = −1.41; −0.91), p-value < 0.001] based on 37,408 participants. The results of the meta-analysis showed a potential protective effect of PA on prevalent and incident depression.

Sign in / Sign up

Export Citation Format

Share Document