Quilt Plots: A Simple Tool for the Visualisation of Large Epidemiological Data

<div><p>Background</p><p>Graphical representation of data is one of the most easily comprehended forms of explanation. The current study describes a simple visualization tool which may allow greater understanding of medical and epidemiological data.</p><p>Method</p><p>We propose a simple tool for visualization of data, known as a “<i>quilt plot</i>”, that provides an alternative to presenting large volumes of data as frequency tables. Data from the Australian Needle and Syringe Program survey are used to illustrate “<i>quilt plots</i>”.</p><p>Conclusion</p><p>Visualization of large volumes of data using “<i>quilt plots</i>” enhances interpretation of medical and epidemiological data. Such intuitive presentations are particularly useful for the rapid assessment of problems in the data which cannot be readily identified by manual review. We recommend that, where possible, “<i>quilt plots</i>” be used along with traditional quantitative assessments of the data as an explanatory data analysis tool.</p></div

<i>Percent tabulation</i>: percentage of people who inject drug attending needle and syringe programs since 1995 with Hepatitis C virus by age × survey years.

<p><i>Percent tabulation</i>: percentage of people who inject drug attending needle and syringe programs since 1995 with Hepatitis C virus by age × survey years.</p

Cumulative incident of toxicity and treatment failure in the first treatment

<p><b>Copyright information:</b></p><p>Taken from "Impact of drug classes and treatment availability on the rate of antiretroviral treatment change in the TREAT Asia HIV Observational Database (TAHOD)"</p><p>http://www.aidsrestherapy.com/content/4/1/18</p><p>AIDS Research and Therapy 2007;4():18-18.</p><p>Published online 17 Sep 2007</p><p>PMCID:PMC2048495.</p><p></p> x axis is "years". Y axis is "cumulative incidence". green line represents toxicity failure. red line represents treatment failure [see Figure 2

Cox proportional hazards models of time until first viral failure after entry.

<p>Cox proportional hazards models of time until first viral failure after entry.</p

Patient characteristics.

<p>cART - combination antiretroviral therapy.</p><p>HIC - High Income Countries.</p><p>M/LIC - Middle/Low Income Countries.</p><p>ADI - AIDS Defining Illnesses.</p><p>HCV - Hepatitis C Virus.</p><p>HBV - Hepatitis B Virus.</p

Meta-analysis of the association between specified and unspecified hormonal contraceptive (HC) use and BV outcome, stratified by prevalent, incident or recurrent BV.

<p>Key: ES = effects size, CI = confidence interval, combined = combined oestrogen- and progesterone-containing methods of HC, POC = progesterone only containing methods of HC, u-HC = unspecified HC.</p

Meta-analysis of the association between hormonal contraceptive (HC) type and prevalent BV.

<p>Key: ES = effects size, CI = confidence interval, combined HC-use = combined oestrogen- and progesterone-containing methods of HC, POC-use = progesterone only containing methods of HC.</p

Characteristics of prospective studies included in the systematic review.

a<p>all adjusted OR/RRs are as reported by authors,</p>b<p>OR/RRs calculated by authors, raw data not available,</p>c<p>baseline prevalence used,</p>d<p>raw data on the % using OC not available, on the basis of the odds ratios reported, the proportion of women using contraceptives were calculated to well exceed 10%,</p>e<p>per number of visits,</p>f<p>number or percentage of assessments rather than number of participants reported, ^gwoman-years, calculated by authors,</p>h<p>raw data was not available, but parent study from which this cohort was derived reported 29% using HC <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0073055#pone.0073055-Artz1" target="_blank">[89]</a>,</p>i<p>baseline prevalence of women using combined methods of contraception was 53.5% of which most went into the longitudinal analysis, but raw data was not reported,</p>j<p>unadjusted ORs clustered by clinic so included as reported. Key: HC = hormonal contraception, COC = combined oestrogen- and progesterone-containing methods of HC, POC = progesterone only containing methods of HC, u-HC = unspecified HC, CS = cross-sectional study, LC = longitudinal cohort, RCT = randomised controlled trial (either LC used or CS data used), OR = odds ratio, RR = risk ratio, NC = no contraception used, TL = tubal ligation.</p

Method for assessment of internal and statistical validity of studies included for review.

<p>Some criteria not applicable depending on study design, these boxes left blank in <b><i><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0141905#pone.0141905.t005" target="_blank">Table 5</a></i></b>.</p

Summary of associations with prevalent or incident/recurrent/persistent BV.

<p>^dDefined in recent sexual partner(s) in cross-sectional studies (either within last 12 months, or last 3 months), or a new sexual partner in longitudinal cohort studies.</p><p>^eSignificant on univariate analysis; significant on multivariate analysis when new FSP/MSP was combined with new MSP/FSP in a broader “new partner” category but for the majority of women this represented a new FSP. FSP (female sexual partner), MSP (male sexual partner)</p><p>Summary of associations with prevalent or incident/recurrent/persistent BV.</p