More than a number...

 

 A couple starts going to therapy to work on their troubled relationship. The therapist asks the couple separately, "how often do you have sex?" The wife responds to the question "ugh, all the time...3 to 4 times a week" and the husband separately responds "hardly ever, only 3 to 4 times a week."

The story above is a great example of how data can be the same in value but completely different in context.  It is important to understand what numbers mean and not just understand the value of the data.  For instance, the newly released summary of the national Youth Risk Behavior Survey (YRBS)[1] shows the percentage of students engaging in various risk behaviors including “never wore a bicycle helmet” and “in a physical fight on school property one or more times.” At first glance, the national findings may seem “normal” but when compared to the state of South Carolina, the findings paint a different picture.[2] 

·       *Nationally, 47% of high school students have ever had sexual intercourse.  That means that almost 5 out of 10 high school students have ever had sex.  This alone seems like a big number.  However, when compared to the percentage in South Carolina, this number doesn’t seem as large because 57% of high school students in the state have ever had sexual intercourse.  That means that in South Carolina, almost 6 out of 10 high school students have ever had sex.

·       Nationally, 15% of high school students have had sexual intercourse with four or more persons.  This is a certainly a cause for concern, however the findings in South Carolina are even more disturbing.  In South Carolina, 21% of high school students have had sexual intercourse with four or more persons. 

·         Nationally, 34% of high school students had sex three months prior to the YRBS survey.  This percentage doesn’t seem as bad when compared to South Carolina, where 42% of high schools students in the state had sex three months prior to the survey.

All of the above comparisons are examples of how data can be interpreted when we don’t take in account the context of the data.  It is important to also define “good” and “bad” so that when you first look at a number like “3 to 4” you can better understand whether that is “good” or “bad.”  When looking at the findings from the YRBS, one way to see how South Carolina students are doing in terms of their sexual behaviors is to compare the state to the nation or to other southern states.  Understanding the context helps someone better identify whether a number is “good”, “average” or “below average.”  The “average” can change from year to year or from state to state depending on the context of the data. 

I leave you with this thought: my husband is an avid outdoorsman and has been trying for years to get me to also love the outdoors.  I recently went fishing and caught a 1lb catfish that fought me like a 90 pound golden retriever.  I was beyond thrilled when I eventually pulled up the fish and thought that I deserved an Olympic medal.  My husband, who was excited that I was excited, was less impressed with my small catch.  He has caught fish over 60 pounds so to him a 1lb fish was considered bait fish.  So as you interpret data as “good”, “bad” or “average”, be sure that you understand the difference between the “bait fish” and the “big one.” 

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[1] Centers for Disease Control and Prevention (CDC). Youth Risk Behavior Surveillance: United States, 2011. MMWR 2012;61(No. SS-4):1-162.

[2] Note – the findings from the YRBS have been rounded.