Definition of Prevalence












5















I have been informed that the prevalence of chickenpox and smallpox in the general population are 10% and 0.1%, respectively. On the Wikipedia page it is written




Prevalence in epidemiology is the proportion of a particular population found to be affected by a medical condition (typically a disease or a risk factor such as smoking or seat-belt use).




Should I read these numbers as 10 out of 100 people at any given time has chickenpox, knowingly or unknowingly? Similarly, 1 out of 1000 people in the general population has smallpox?



To me these numbers sounds very high.










share|improve this question























  • Well, one of those numbers is definitely too high. The prevalence of smallpox is 0% and has been since 1980.

    – Carey Gregory
    Feb 1 at 18:58






  • 3





    @CareyGregory the point prevalence (and the incidence) of smallpox is 0, but the lifetime prevalence is nonzero for some populations.

    – De Novo
    Feb 1 at 19:41











  • @DeNovo Ah, okay, thanks.

    – Carey Gregory
    Feb 1 at 22:40
















5















I have been informed that the prevalence of chickenpox and smallpox in the general population are 10% and 0.1%, respectively. On the Wikipedia page it is written




Prevalence in epidemiology is the proportion of a particular population found to be affected by a medical condition (typically a disease or a risk factor such as smoking or seat-belt use).




Should I read these numbers as 10 out of 100 people at any given time has chickenpox, knowingly or unknowingly? Similarly, 1 out of 1000 people in the general population has smallpox?



To me these numbers sounds very high.










share|improve this question























  • Well, one of those numbers is definitely too high. The prevalence of smallpox is 0% and has been since 1980.

    – Carey Gregory
    Feb 1 at 18:58






  • 3





    @CareyGregory the point prevalence (and the incidence) of smallpox is 0, but the lifetime prevalence is nonzero for some populations.

    – De Novo
    Feb 1 at 19:41











  • @DeNovo Ah, okay, thanks.

    – Carey Gregory
    Feb 1 at 22:40














5












5








5


1






I have been informed that the prevalence of chickenpox and smallpox in the general population are 10% and 0.1%, respectively. On the Wikipedia page it is written




Prevalence in epidemiology is the proportion of a particular population found to be affected by a medical condition (typically a disease or a risk factor such as smoking or seat-belt use).




Should I read these numbers as 10 out of 100 people at any given time has chickenpox, knowingly or unknowingly? Similarly, 1 out of 1000 people in the general population has smallpox?



To me these numbers sounds very high.










share|improve this question














I have been informed that the prevalence of chickenpox and smallpox in the general population are 10% and 0.1%, respectively. On the Wikipedia page it is written




Prevalence in epidemiology is the proportion of a particular population found to be affected by a medical condition (typically a disease or a risk factor such as smoking or seat-belt use).




Should I read these numbers as 10 out of 100 people at any given time has chickenpox, knowingly or unknowingly? Similarly, 1 out of 1000 people in the general population has smallpox?



To me these numbers sounds very high.







statistics






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Feb 1 at 18:32









JohnJohn

283




283













  • Well, one of those numbers is definitely too high. The prevalence of smallpox is 0% and has been since 1980.

    – Carey Gregory
    Feb 1 at 18:58






  • 3





    @CareyGregory the point prevalence (and the incidence) of smallpox is 0, but the lifetime prevalence is nonzero for some populations.

    – De Novo
    Feb 1 at 19:41











  • @DeNovo Ah, okay, thanks.

    – Carey Gregory
    Feb 1 at 22:40



















  • Well, one of those numbers is definitely too high. The prevalence of smallpox is 0% and has been since 1980.

    – Carey Gregory
    Feb 1 at 18:58






  • 3





    @CareyGregory the point prevalence (and the incidence) of smallpox is 0, but the lifetime prevalence is nonzero for some populations.

    – De Novo
    Feb 1 at 19:41











  • @DeNovo Ah, okay, thanks.

    – Carey Gregory
    Feb 1 at 22:40

















Well, one of those numbers is definitely too high. The prevalence of smallpox is 0% and has been since 1980.

– Carey Gregory
Feb 1 at 18:58





Well, one of those numbers is definitely too high. The prevalence of smallpox is 0% and has been since 1980.

– Carey Gregory
Feb 1 at 18:58




3




3





@CareyGregory the point prevalence (and the incidence) of smallpox is 0, but the lifetime prevalence is nonzero for some populations.

– De Novo
Feb 1 at 19:41





@CareyGregory the point prevalence (and the incidence) of smallpox is 0, but the lifetime prevalence is nonzero for some populations.

– De Novo
Feb 1 at 19:41













@DeNovo Ah, okay, thanks.

– Carey Gregory
Feb 1 at 22:40





@DeNovo Ah, okay, thanks.

– Carey Gregory
Feb 1 at 22:40










1 Answer
1






active

oldest

votes


















7














There are two broad types of prevalence statistics: point prevalence and period prevalence. In both cases, more details need to be specified in order to fully describe the statistic.



Point prevalence is the proportion of people who have a disease at a given point in time. In other words, the total number of people in a given population who have a disease at a specific point in time divided by the number of people in that population. To be complete, it should include a case definition (how "have a disease" is defined), a population definition, and the particular point in time used.



Period prevalence is the proportion of people who have or have at some point had a disease over a period of time. Here, instead of the total number with a disease at any one time, you include anyone who had the disease at any point during the period. Depending on the period you choose, the population may change, in which case, you would typically use the population at the midpoint of the period.



A specific (and common) period to use for this statistic is "lifetime", which changes things slightly. Lifetime prevalence is typically reported as the proportion of people (alive now) who have had the disease at any point in their lifetime. The period in this case is not an absolute time period, but the lifetime of each person in the population.



You can learn more about this in the CDC's online text Principles of Epidemiology in Public Health Practice. Lesson 3 covers prevalence statistics.






share|improve this answer

























    Your Answer








    StackExchange.ready(function() {
    var channelOptions = {
    tags: "".split(" "),
    id: "607"
    };
    initTagRenderer("".split(" "), "".split(" "), channelOptions);

    StackExchange.using("externalEditor", function() {
    // Have to fire editor after snippets, if snippets enabled
    if (StackExchange.settings.snippets.snippetsEnabled) {
    StackExchange.using("snippets", function() {
    createEditor();
    });
    }
    else {
    createEditor();
    }
    });

    function createEditor() {
    StackExchange.prepareEditor({
    heartbeatType: 'answer',
    autoActivateHeartbeat: false,
    convertImagesToLinks: false,
    noModals: true,
    showLowRepImageUploadWarning: true,
    reputationToPostImages: null,
    bindNavPrevention: true,
    postfix: "",
    imageUploader: {
    brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
    contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
    allowUrls: true
    },
    noCode: true, onDemand: true,
    discardSelector: ".discard-answer"
    ,immediatelyShowMarkdownHelp:true
    });


    }
    });














    draft saved

    draft discarded


















    StackExchange.ready(
    function () {
    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmedicalsciences.stackexchange.com%2fquestions%2f18547%2fdefinition-of-prevalence%23new-answer', 'question_page');
    }
    );

    Post as a guest















    Required, but never shown

























    1 Answer
    1






    active

    oldest

    votes








    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    7














    There are two broad types of prevalence statistics: point prevalence and period prevalence. In both cases, more details need to be specified in order to fully describe the statistic.



    Point prevalence is the proportion of people who have a disease at a given point in time. In other words, the total number of people in a given population who have a disease at a specific point in time divided by the number of people in that population. To be complete, it should include a case definition (how "have a disease" is defined), a population definition, and the particular point in time used.



    Period prevalence is the proportion of people who have or have at some point had a disease over a period of time. Here, instead of the total number with a disease at any one time, you include anyone who had the disease at any point during the period. Depending on the period you choose, the population may change, in which case, you would typically use the population at the midpoint of the period.



    A specific (and common) period to use for this statistic is "lifetime", which changes things slightly. Lifetime prevalence is typically reported as the proportion of people (alive now) who have had the disease at any point in their lifetime. The period in this case is not an absolute time period, but the lifetime of each person in the population.



    You can learn more about this in the CDC's online text Principles of Epidemiology in Public Health Practice. Lesson 3 covers prevalence statistics.






    share|improve this answer






























      7














      There are two broad types of prevalence statistics: point prevalence and period prevalence. In both cases, more details need to be specified in order to fully describe the statistic.



      Point prevalence is the proportion of people who have a disease at a given point in time. In other words, the total number of people in a given population who have a disease at a specific point in time divided by the number of people in that population. To be complete, it should include a case definition (how "have a disease" is defined), a population definition, and the particular point in time used.



      Period prevalence is the proportion of people who have or have at some point had a disease over a period of time. Here, instead of the total number with a disease at any one time, you include anyone who had the disease at any point during the period. Depending on the period you choose, the population may change, in which case, you would typically use the population at the midpoint of the period.



      A specific (and common) period to use for this statistic is "lifetime", which changes things slightly. Lifetime prevalence is typically reported as the proportion of people (alive now) who have had the disease at any point in their lifetime. The period in this case is not an absolute time period, but the lifetime of each person in the population.



      You can learn more about this in the CDC's online text Principles of Epidemiology in Public Health Practice. Lesson 3 covers prevalence statistics.






      share|improve this answer




























        7












        7








        7







        There are two broad types of prevalence statistics: point prevalence and period prevalence. In both cases, more details need to be specified in order to fully describe the statistic.



        Point prevalence is the proportion of people who have a disease at a given point in time. In other words, the total number of people in a given population who have a disease at a specific point in time divided by the number of people in that population. To be complete, it should include a case definition (how "have a disease" is defined), a population definition, and the particular point in time used.



        Period prevalence is the proportion of people who have or have at some point had a disease over a period of time. Here, instead of the total number with a disease at any one time, you include anyone who had the disease at any point during the period. Depending on the period you choose, the population may change, in which case, you would typically use the population at the midpoint of the period.



        A specific (and common) period to use for this statistic is "lifetime", which changes things slightly. Lifetime prevalence is typically reported as the proportion of people (alive now) who have had the disease at any point in their lifetime. The period in this case is not an absolute time period, but the lifetime of each person in the population.



        You can learn more about this in the CDC's online text Principles of Epidemiology in Public Health Practice. Lesson 3 covers prevalence statistics.






        share|improve this answer















        There are two broad types of prevalence statistics: point prevalence and period prevalence. In both cases, more details need to be specified in order to fully describe the statistic.



        Point prevalence is the proportion of people who have a disease at a given point in time. In other words, the total number of people in a given population who have a disease at a specific point in time divided by the number of people in that population. To be complete, it should include a case definition (how "have a disease" is defined), a population definition, and the particular point in time used.



        Period prevalence is the proportion of people who have or have at some point had a disease over a period of time. Here, instead of the total number with a disease at any one time, you include anyone who had the disease at any point during the period. Depending on the period you choose, the population may change, in which case, you would typically use the population at the midpoint of the period.



        A specific (and common) period to use for this statistic is "lifetime", which changes things slightly. Lifetime prevalence is typically reported as the proportion of people (alive now) who have had the disease at any point in their lifetime. The period in this case is not an absolute time period, but the lifetime of each person in the population.



        You can learn more about this in the CDC's online text Principles of Epidemiology in Public Health Practice. Lesson 3 covers prevalence statistics.







        share|improve this answer














        share|improve this answer



        share|improve this answer








        edited Feb 1 at 19:43

























        answered Feb 1 at 19:30









        De NovoDe Novo

        1,52815




        1,52815






























            draft saved

            draft discarded




















































            Thanks for contributing an answer to Medical Sciences Stack Exchange!


            • Please be sure to answer the question. Provide details and share your research!

            But avoid



            • Asking for help, clarification, or responding to other answers.

            • Making statements based on opinion; back them up with references or personal experience.


            To learn more, see our tips on writing great answers.




            draft saved


            draft discarded














            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmedicalsciences.stackexchange.com%2fquestions%2f18547%2fdefinition-of-prevalence%23new-answer', 'question_page');
            }
            );

            Post as a guest















            Required, but never shown





















































            Required, but never shown














            Required, but never shown












            Required, but never shown







            Required, but never shown

































            Required, but never shown














            Required, but never shown












            Required, but never shown







            Required, but never shown







            Popular posts from this blog

            Biblatex bibliography style without URLs when DOI exists (in Overleaf with Zotero bibliography)

            ComboBox Display Member on multiple fields

            Is it possible to collect Nectar points via Trainline?