All 4 faces pain scales were found to be adequately supported by psychometric data .
When given a choice between faces scales , children preferred the WBFPRS .
Confounding of pain intensity with affect caused by use of smiling and crying anchor faces is a disadvantage of the WBFPRS .
: For clinical use , we found no grounds to switch from 1 faces scale to another when 1 of the scales is in use .
CONTEXT : Numerous faces scales have been developed for the measurement of  pain intensity in children .
It remains unclear whether any one of the faces scales is better for a particular purpose with regard to validity , reliability , feasibility , and preference .
OBJECTIVES : To summarize and systematic ally review faces pain scales most commonly used to obtain self-report of pain intensity in children for evaluation of reliability and validity and to compare the scales for preference and utility .
A novel needle-free powder lidocaine delivery system for rapid local analgesia.
OBJECTIVE To determine the analgesic effect and tolerability of a novel needle-free powder lidocaine delivery system in children undergoing venipuncture . STUDY DESIGN In this double-blind , placebo-controlled , single-center trial , 306 children age 3 to 18 years were r and omized to receive a needle-free powder lidocaine delivery system or matching sham placebo at the back of the h and 2 to 3 minutes before venipuncture . Venipuncture pain was self-reported using the Wong-Baker FACES scale ( in 3- to 12-year-olds ) and a 100-mm visual analog scale ( in 8- to 18-year-olds ) . Safety was assessed by adverse events , investigator skin site assessment s , and children 's self-report of the administration comfort of study treatments . Effect sizes were compared by 2- sample t test and Glass 's Delta approach . RESULTS Subjects receiving the needle-free powder lidocaine delivery system exhibited mean pain reductions ( effect size ) of 33 % to 46 % relative to sham placebo .  Pain reductions were statistically significant for all ages combined and also for the youngest and oldest age strata . Self-reported administration comfort levels were similar in the active system and sham placebo groups . Incidences of adverse events and dermal reactions were low ; the most common dermal reaction was mild erythema . CONCLUSIONS The needle-free powder lidocaine delivery system was well tolerated and provided effective local analgesia when administered 2 to 3 minutes before venipuncture
All 4 faces pain scales were found to be adequately supported by psychometric data .
When given a choice between faces scales , children preferred the WBFPRS .
Confounding of pain intensity with affect caused by use of smiling and crying anchor faces is a disadvantage of the WBFPRS .
: For clinical use , we found no grounds to switch from 1 faces scale to another when 1 of the scales is in use .
CONTEXT : Numerous faces scales have been developed for the measurement of  pain intensity in children .
It remains unclear whether any one of the faces scales is better for a particular purpose with regard to validity , reliability , feasibility , and preference .
OBJECTIVES : To summarize and systematic ally review faces pain scales most commonly used to obtain self-report of pain intensity in children for evaluation of reliability and validity and to compare the scales for preference and utility .