Although claims data provide the most accurate information about health care use, ensuring adequate follow-up for purposes of obtaining information from patient self-report is important because many people do not report alcohol-related events to insurance compa-nies.
( ( Although ( ( claims data ) ( provide ( ( the ( ( most accurate ) information ) ) ( about ( health ( care use ) ) ) ) ) ) ) ( , ( ( ( ensuring ( adequate follow-up ) ) ( for ( purposes ( of ( ( obtaining information ) ( from ( patient self-report ) ) ) ) ) ) ) ( ( ( is important ) ( because ( ( many people ) ( ( do not ) ( ( report ( alcohol-related events ) ) ( to ( insurance compa-nies ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (SBAR (IN Although) (S (NP (NNS claims) (NNS data)) (VP (VBP provide) (NP (NP (DT the) (ADJP (RBS most) (JJ accurate)) (NN information)) (PP (IN about) (NP (NN health) (NN care) (NN use))))))) (, ,) (S (VP (VBG ensuring) (NP (JJ adequate) (NN follow-up)) (PP (IN for) (NP (NP (NNS purposes)) (PP (IN of) (S (VP (VBG obtaining) (NP (NN information)) (PP (IN from) (NP (JJ patient) (NN self-report)))))))))) (VP (VBZ is) (ADJP (JJ important)) (SBAR (IN because) (S (NP (JJ many) (NNS people)) (VP (VBP do) (RB not) (VP (VB report) (NP (JJ alcohol-related) (NNS events)) (PP (TO to) (NP (NN insurance) (NNS compa-nies)))))))) (. .)))
The insurance companies want to reduce medical payments by following-up to ensure patient was sober at the time of incident and intoxication may lead to a claim denial on reimbursement for medical expenses. 
( ( The ( insurance companies ) ) ( ( want ( to ( ( ( reduce ( medical payments ) ) ( by following-up ) ) ( to ( ensure ( ( ( patient ( was ( sober ( at ( ( the time ) ( of incident ) ) ) ) ) ) and ) ( intoxication ( may ( ( lead ( to ( a ( claim denial ) ) ) ) ( on ( reimbursement ( for ( medical expenses ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN insurance) (NNS companies)) (VP (VBP want) (S (VP (TO to) (VP (VB reduce) (NP (JJ medical) (NNS payments)) (PP (IN by) (NP (NN following-up))) (S (VP (TO to) (VP (VB ensure) (S (S (NP (NN patient)) (VP (VBD was) (ADJP (JJ sober) (PP (IN at) (NP (NP (DT the) (NN time)) (PP (IN of) (NP (NN incident)))))))) (CC and) (S (NP (NN intoxication)) (VP (MD may) (VP (VB lead) (PP (TO to) (NP (DT a) (NN claim) (NN denial))) (PP (IN on) (NP (NP (NN reimbursement)) (PP (IN for) (NP (JJ medical) (NNS expenses)))))))))))))))) (. .)))