> I hope I can clarify some of the confusion Valerie has experienced in
> interpreting the data posted to the CDC site last week. The
> Pediatrics study she refers to utilizes data from a subsample of the
> National Immunization Survey collected in 2002, because the first year
> the bf items were included they were only part of an optional module
> that was not administered to everyone who completed the survey. As is
> clearly explained directly on the CDC site, the data on the CDC site,
> however, are based on the full NIS sample, after the bf items were
> included into the core survey and thus asked of every sample
> respondent.
>
> While it is true that the items are based on maternal recall, this is
> the same methodology used by the RLMS and most other surveys assessing
> bf prevalence. I will wholeheartedly agree that this is far from the
> ideal methodology, however, the cost and labor involved to assess a
> population estimate of bf duration through 35 months via tracking
> motherbaby dyads through weaning is something sadly no taxpayer would
> be willing to take on, as it would need to go into the multi-millions
> of dollars and would likely yield data not significantly unlike the
> current estimates.
>
> For a full explanation of the NIS methodology, including accurate
> numbers reflecting the sample size used, please see
> http://www.cdc.gov/breastfeeding/NIS_data/index.htm and scroll all the
> way through the page to the bold type that says METHODOLOGY and
> SELECTING THE NIS STUDY POPULATION. In these sections the reader will
> note: "Each year, approximately 35,600 completed phone interviews are
> obtained nationally in the NIS." This is a far cry from the 727
> Valerie mistakenly assumed to be the sample as reported in the 2003
> Pediatrics article. Detailed information about the NIS methodology
> and why it is legitimate to base state and some local estimates on
> their sample can be found at
> http://www.cdc.gov/nip/coverage/default.htm#NIS
>
> An additional point of clarification, as can be clearly seen from the
> current data posted on the CDC website, in all footnotes on all tables
> posted to the site, exclusive breastfeeding in this sample does not
> have a 7 day limitation to it, as Valerie mistakenly assumed from the
> 2003 Pediatrics article. As with any complex data set, it is
> important to read all pertinent footnotes and methodological
> explanations before generalizing assumptions across sources,
> especially when one article is published in 2003, thus written largely
> in 2002, and the data in question cover the calendar year 2003, and
> thus were not even available at the time of publication of the 2003
> article.
>
> It is true that the 2003 definition of exclusive breastfeeding was
> inadequate and incorrect. As I have posted to LN before, that has
> since been changed and starting in 2004 an accurate definition of
> exlusive breastfeeding was used. This is a new data set and thus will
> have many glitches and items to be corrected as it develops. It is
> important to not lose the forest for the trees, however, as this
> dataset is the result of a tremendous amount of hard work from good
> people who recognized a need for a non-proprietary data source and
> sought to fill that need. These data are good and useful, and serve
> an important public health purpose.
>
> Katherine
>
> ------------------------------
>
> Date: Tue, 10 Aug 2004 07:23:46 EDT
> From: "Valerie W, McClain" <[log in to unmask]>
> Subject: CDC and stats
>
> I would like to point out again in regard to the breastfeeding stats
> provided by the CDC that those statistics are based on 727 children in
> the USA ( based
> on a study in Pediatrics 2003; 111: 1198-1201). I look at the stats
> for
> Florida and go into shock. (43.7% exclusive breastfeeding at 3 months)
> They don't jive with the breastfeeding reality I see here. But then
> if one thinks about it and divides 50 states into 727 children, one
> realizes that the Florida statistics probably represent about 14
> children. I don't remember how this study verified the breastfeeding
> information from mother's recall...anybody remember???I know with the
> vaccination information verification was done through medical records.
>
> Exclusive breastfeeding in these statistics was described as: "the
> rate of
> exclusive breastfeeding in the early postpartum period was estimated
> as a proportion of infants who were not fed something other than
> breastmilk or water before 7 days." (Pediatrics 2003; 111: 1198-1201)
> The categories on the tables are for exclusive breastfeeding at 3
> months and 6 months. Thus I have to wonder if the determination for
> children being placed in the exclusive category of 3 or 6 months was
> based on the first 7 days only. Exclusive breastfeeding in these
> stats includes water supplementation. I have a hard time equating
> exclusivity with water supplementation.
>
> Statistics should enlighten us, give us a true picture of reality.
> These statistics are not enlightening to me. I feel they may
> contribute to self-delusion about the reality of breastfeeding in the
> USA. Valerie W. McClain, IBCLC
***********************************************
To temporarily stop your subscription: set lactnet nomail
To start it again: set lactnet mail (or digest)
To unsubscribe: unsubscribe lactnet
All commands go to [log in to unmask]
The LACTNET mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software together with L-Soft's LSMTP(R)
mailer for lightning fast mail delivery. For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html
|
