总共24次就诊。

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Note added at 30 mins (2016-01-29 12:36:18 GMT)
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累积24次看病/看诊/就医等等都可以。

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Note added at 52 mins (2016-01-29 12:58:39 GMT)
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"Combined" carries no specific meaning.. The author just meant to say "No more than 25 visits" in a period of time (maybe a year)

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Note added at 2 hrs (2016-01-29 14:16:33 GMT)
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It could mean Chiropractic visits and other types of visits counted together, for example, acupuncture visit. 比如，一年可以看12次Chiropractic professionals, 12 次acupuncturists， 两者的次数可以任意，总计不超过24次即可。到底是什么情形，最好询问一下客户。

I found this site.

News & Notes 1 - Ohio Laborers' Fringe Benefit Programs
www.olfbp.org/index.php/news-notes1
(For example, you can visit a chiropractor 30 times and get physical therapy 20 times.) If you exceed the 50 combined visits, the Fund will not cover the expenses ...

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Note added at 2 hrs (2016-01-29 14:26:33 GMT)
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另外一个例子：这里讲一名会员每年接受的PT/OT/ST这三项服务，放在一起计算，总共不能超过60次。

BlueShield 2016 Individual Plans/Rates - Bethlehem ...
www.bethlehemchamber.com/.../...
Bethlehem Area Chamber of Commerce
2016 individual plans annual BlueShield benefit limits. Habilitation (PT/OT/ST) 1. 60 combined visits per person per plan year. Rehab, outpatient (PT/OT/ST) 1.