TRANSCUTANEOUS ELECTRICAL

NERVE STIMULATION (TENS) DEVICES

f,B.VICES. 
"dia 
OFFICE OF INSPECTOR GENERAL 
OFFICE OF ANALYSIS AND INSPECTIONS 
JULY 1989  TRANSCUTANEOUS ELECTRICAL

NERVE STIMULATION (TENS)

DEVICES

Richard P. Kusserow 
INSPECTOR GENERAL 
88060 
OAI-02- JULY 1989
 EXECUTIVE SUMMARY 
PURPOSE 
This inspection was conducted to identify vulnerabilties in Medicar reimbursement for trs
cutaeous electrcal nerve stiulation (TNS) devices. 
BACKGROUND 
The TENS, a low-voltage electrcal impulse generator used as a pain-control device, usually 
looks lie a portble transistor radio and can be attached to one s belt. Properly trned, pa
tients are able to use this device as they go about their daily activities. 
Medicare covers long-term use of TENS when it provides 
signifcant therapeutic benefit to pa 
tients with chronic pai and shon-term use for acute post-operative pai. 
Medicare coverage guidelies for treatig chronic pai reuire that TENS be used for a 
month tral period and its effectiveness monitored by the physician or physical therapist. The 
device may be rented durg the assessment period and then purchased if beneficial. 
Reimburement for TENS has incrased substatialy over the past few years. Allowed Medi
care charges in 1985 were $12 802,927; they incrased by 55 percent in 1986 to $20,381 751 
and by an additional 97 percent in 1987 to $40,111,359. 
The Offce of Inspector General' s (OIG) concerns about Medicare reimbursing for TENS were 
generated by beneficiar complaints. A Medicare Fraud Alen was issued in  TPnnrt
,T111v 1 Q 
ing on aggrssive sellig techniques by suppliers of TENS. 
ISSUES AND METHODOLOGY 
priar 
The  issues adessed were: (1) to what extent ar carers reimburing for TENS 
claims which do not meet Medcare coverage guidelines, and (2) how useful are Medicare 
ben
eficiares actually finding TENS in alleviating pain? 
A radom' sample of 210 cases was. selected frm 1986 HCFA data for both rentig and pur
chasing TENS. Sixty were drpped because the beneficiar was either deceased or could not 
be located. Clais and supportng dpcuments were obtained from the carers for each of 
these beneficiares. 
Telephone discussions were held with 126 of the remaiing 150 sample beneficiares to gather 
pertent information on whether thy-had received the TENS, their impressions as to its effec
tiveness, and whether they had a tral period. A subsample of 26 physicians who authorized 
TENS was contacted by telephone, along with severa physical therapists with 
expertse in 
using TENS. . Additionally, information was collected from 26 Medicar carers for whom  sample beneficiar claims were submitted to determne their policies relating to TENS. Fony
progrs 
eight State Medcaid  and the Veterans Administration provided information regard
ing their reimburement of TENS. 
FINDINGS 
One-third Of Clams For Beneficiaries Contacted Were Inappropriately Reimbursed 
Medicare carers should not have paid for 33 percent of the TENS because they were either 
possibly fraudulent or failed to meet the Medicar coverage requirements for a 
tral period. 
This resulted in an estiated loss of $4 394 500 to Medicar (appendix I). 
Nine percent (11 of 126) of claims for the beneficiares contacted are possibly fraudulent. 
These 11 beneficiares denied ever having a TENS. (These cases have been referred to the 
OIG' s Offce of Investigations.) Additionaly, 24 percent (30 of the 126) of the beneficiares 
contacted did not have the requid tral period of at least 1 month. Typically these people im
medately purchased a TENS. 
caer 
Medicare  proedures to enforce the tral period need strengthening. Although the sup
portng documentation submitted with the 85 sample purchase claims mentioned a 
tral period 
in thee-quarrs of the cases, only hal of those indicated a successful tral period. 
Only hal of the physicians contacted knew the Medicar guidelines for reimburing TENS, 
and only half of the carers had sent any educational information about TENS coverage to 
providers. 
Most Purchased Tens Units Were Found Helpful; Trial Period Plays Major Role In 
Assuring Appropriate Use 
Nearly 80 percent (67 or 85) of beneficiares who purchased and received a TENS found it 
beneficial. Eighty-four percent of the beneficiares who had the TENS recommended by a 
medical practitioner found it helpful; in contrst, only 56 percent of those who did not have it
so recommended found it helpful. 

Use of the required tral-period is criticaly importt in assuring the most effective use of 
TENS. Of the 55 beneficiares who purhased a TENS and had a tral period, virtally all (53 
of 55) found the TENS helpful. In contrt, only 47 percent of those who purchased a TENS 
without a tral period (14 of 30) were helped. 
Most of the 26 physicians contacted view the TENS favorably. Two-thirds of the physicians 
said it was their idea to prescrbe a TENS and most thought the TENS helpful in 
relieving the 
patient s pain. More than hal said the patient was seen during the tral period by either them
selves or a physical therapist to teach th  patient to use the TENS and evaluate its effective
ness.  RECOMMENDATIONS 
To reduce inappropriate payments for TENS, HCFA should: 
Evaluate and strengten, as needed, carer implementation of Medicare and Omnibus 
Reconcilation Act of 1987 (OBRA 1987) requirements to: 
ensure a tral period prior to purchasing a TENS by assurng an appropriate 
certfication form is submitted by the physician which indicates information on 
trning in using the device and its effectiveness; 
prohibit payment unless the supplier receives a wrtten order from the physician 
prior to delivering the device to the patient. 
Publici  Medicar coverage requirments to the medical community; and 
Add TENS to the categories of servces to be considered by 
carers when conducting 
postpayment reviews of providers. 
HCFA RESPONSE 
The HCFA concurd with the OIG recommendations and made some genera comments (see 
appendix 11.  ................................................. 
... .. ....  ....  ..... ..  ..  ..  .. ...  ...   ...   ...   ...   ...   .. . ...  . ...    .....    .....     .....     .....    .....     .....     .....   . ... .   . ... .   .. ..   .....     ....   ....   ...
. . . . ..  ..  ..  ..  ..  .... . .. .... . ..... .. . ...... . . ...... . . .......  . .......   ........  . ........   . ..... .    ....    ....    ...   ....    ....    ......      ......      ......      ......      ......      ......      ......    . ....  .   ... ..     ......      ......      .....     .....     .....     .....     .....     .....     .... .   .. ..    ....    ...   ...   ...   ...   ...   ...   ...   ...   ...   ...   ...   ...   ...   ...
TABLE OF CONTENTS 
EXECUTIVE SUMMARY 
INTRODUCTION 
.. . . 1 
Purose 
Background. . . . . . 
Issues. . . . . . . . . . . . . . . . . . . . . . . . . . 
Methodology.... . .. 
FI N DI 
NGS  8 . . . . . 
One-thd of the clais for beneficiares contacted were 
inappropriately reimbured. . 
Most purhased TENS units found helpful; 
tral period plays 
major role in assurg appropriate use 
RECOMMENDATIONS 
APPENDICES 
Methodology.................................................. .

I. 
ll. HCFA general comments an  OIG response  INTRODUCTION

PURPOSE 
The purose of this inspection was to identify vulnerabilties in Medicar reimbursement for 
trscutaeous 
electrcal nerve stimulation devices. 
BACKGROUND 
When senior citizens get together, the tal frquently turs to the subject of pain, panicularly 
chronic pai. Many different therapies have been tred for relieving chronic pain with varing 
degrees of success. A relatively new modality is a transcutaneous  stiulation 
electrcal nerve 
device, hereafter referred to as TENS. 
The TENS is a low-voltage electrcal impulse generator used as a non-
pharacological pai
control device. It usually looks like a portble transistor radio and can be attached to one 
belt. Properly trned, patients ar able to use this device as they go about their daly activi
ties. There ar multiple brands and models on the market, each slightly different but al hav
ing wies leadig to either two or four electrodes. The electrodes are placed on the patient 
body at positions selected by a physician or physical therapist based on varous factors such as 
the anatomical location of periphera nerves and/or the ara of gratest pai. However, an ele
ment of tral and error is always present when determning placement. After the electrodes 
placed with conducting jelly between them and the patient s skin, the controls ar set, the unit 
is tued on, and a pulsating curnt passes thugh the area providing a mid-to-moderate 
stiulation. Some practitioners prefer low frquency/high intensity stimulation while others 
favor high frequency/low intensity application. The 
literatur and clinicians both repon vara
tions in treatment time, raging from 15 or 20 miutes daly to use throughout the day. They 
also strss the importce of evaluating patients. 
Exactly how relief is achieved is not fully known, but there are two prevalent theories: one, 
the Gate' Control Theory, suggests that the pulsating curnt overloads the nerve circuitr and 
pai  bra; 
blocks  signals to the  another theory says that electrcal stimulation causes the brain 
to react by releasing natural pain-suppressing substances called enkephelins and endorphins. 
A literatue review indicates that TES does not cure a disease and does not work in all cases, 
but may give symptomatic relief of pain. Most clinicians agree that TENS applied properly 
can be effective, regardless of the brad or model, although one model may be more effective 
for a parcular patient than another. However, in untrained hands TENS is not an effective or 
valuable modity. Although some clinicians repon as much as a 90 percent success rate with 
carefully selected patients, most repon about a 40-50 percent success rate.  ...
Medicare Coverage 
Medicare reimburses for both long-term use of TENS when they provide significant therapeu
tic benefit to patients with chronic pai and for shott-term use for post-operative pain. When 
used for the treatment of acute post-operative pai, TENS are covered as supplies. The TENS 
are covere, however, as prosthetic devices when used for the tratment of chronic intractable 
pain (MCM Chapter ll-Coverage Issues Appendix, Section 65-8 AI). 
Medicare coverage guidelines require that, when used for the tratment of chronic intractable 
pai
, lENS must be used by the patient on a tral basis and its effectiveness monitore by the 
physician or physical therapist. Section 35-46 of the same appendix addrsses the use of the 
tral period to determne the patient s suitabilty for electrcal nerve 
stimulation therapy: 
It is used by the patient on a trial basis and its effectiveness in modulating pain 
is monitored by the physician, or physical therapist. Generally the physician or 
physical therapist should be able to determine whether the patient is 
likely to de,: 
rive signifcant therapeutic benefit from continuous use of a TENS within a trial pe
riod of one month; in a few cases this determination ma take longer to 
make...when the physician or physical therapist advises the patient to rent the 
TENS during the trial period program payment ma be made. 
Based on the Omnibus Budget Reconcilation Act (OBRA) of 1987, the rental period for 
TENS was incrased (effective Januar 1, 1989) to a peripd of not more than 2 months. If the 
item is then deterred to be appropriate, it is reimbursed as routinely purchased,equipment. 
The OBRA 1987 also requirs payment to be made for cenain equipment such as TENS only 
if the physician has communicated a wrtten order for the equipment prior to delivery. This re
quirment is designed to cunai some aggressive maketing strtegies. 
Home use of TENS by patients is discussed in Section 35-48 of the appendix: 
A patient can be taught how to employ the stimulator, once this is done, can use it 
safely and effectively without direct physician supervision....Once it is determined 
that electrical stimulation should be continued as therapy and the patient has been 
trained to use the stimulator, it is expected that the patient wil employ the TENS 
on a continual basis in his home. 
The most appropriate placement of the electres, -as well as the intensity and frequency of the 
curnt, 
is established by the physician or physical therapist after an evaluation period of about 
1 month. The device may be reimbured on a rental basis durg this assessment period. 
After the physician or physical thelJpist is satisfied that the unit performs a therapeutic pur
pose, the beneficiar must purhase it. The medical necessity for the services furnished be
yond the fist month must always be documented. Medical policy guidelines regarding 
medical necessity are left up to each carer to determine. Medicare carers are responsible to 
see that coverage requirements ar met before approving payment.  Medicare also reimbures for replacement electrodes, gel and batteries when necessar for the 
continuing use of TENS for the relief of chronic pain (MCM Section 2130). 
Reimbursement 
Clais 
submitted by suppliers under assignment ar paid at 80 percent of the allowable charge
recogn 
by Medcare. The beneficiar is then responsible for paying the 20 percent coin
surance to the supplier unless it is a hardship. The supplier is obligated to make a reasonable 
effon to collect the coinsurce. Suppliers who do not accept assignment can charge the ben
eficiar the dierence between their tota charge and the amount Medicare allows. The HCFA 
repons a tota of $12 802 927 in alowed Medicar charges for TENS in 1985, a 55 percent in
crease in 1986 to $20,381 751, and a 97 percent increase in 1987 to $40 111,359. (One carer 
had an 832 percent increase in alowed charges from 1986 to 1987: $1 580,524 to 
$14 729,627.) The alowed TENS renta charges for the sample clais raged from $50 
$101 a month with an average of $89 a month while the allowed purchase charges raged
from $446 to $640 per unit with an average of $480 per unit depending on the carer 
service 
area. 
OIG Concerns 
The Offce of Inspector General (OIG) has had a number of concerns about Medicar s reim
bursement for TENS. A Medicare Fraud Alen was issued in July 1988 
reportng on aggres
sive sellng techniques by suppliers of TENS. These included door-to-door solicitation, sales 
presentations to groups of senior citizens and the use of physicians 
travellng with sales agents 
to sign the supplier-prepared authorization forms without requirng an evaluation period.
There have also been complaits from beneficiares who never received the units for which 
Medicare was biled. 
ISSUES 
To what extent ar carers reimbursing for TENS claims which do not meet Medicare 
coverage guidelies?

How useful ar Medicare beneficiares actually finding TENS in alleviating pain? 
METHODOLOGY 
This inspection assessed the effectiveness of HCFA poliCy and guidelines, as well as carer 
implementation of them, in assurg appropriate Medicar reimbursement. It also examied 
Medicare beneficiares ' perceptions of the usefulness of TENS in alleviating pain. Members 
of the inspection team included a physical therapist and a registered nurse. 
A 0.4 percent sample of 210 cases was selected at radom from beneficiares who had Medi
care claims reimbursed for TENS in 1986. Sixty were drpped because the beneficiar was ei ther deceased or could not be located. This selection was made from 1986 BMAD data for 
both the rental and purchase of two- and four-lead TENS. 
Telephone discussions were held with 126 of the 
remaiing 150 sample beneficiares. (The re
mainig 24 could not be reached by telephone or mai.) The 126 were fist asked to veriy
they had received the TENS. They were also asked their impressions as to its 
effectiveness in 
relieving their pain (whether acute post-surgical or chronic), their experience with the 
cliician s evaluation, their perceptions of the marketing practices of suppliers, and other pert
nent information. 
Claims and supportg documents were requested from the 26 Medicar carers to whom the 
150 sample beneficiar clais were submitted and these were reviewed to see whether a tral 
period was documented. 
A subsample of 30 physicians was selected from those authorizing TENS for the 126 benefici
ares contacted: telephone discussions were held with 26 of them to gain perceptions regard
ing their patient s use of TENS. The subsample included physicians of different 
specialties
from different pan of the countr. In addition, several physical therapists with expertse in 
TENS were contacted by telephone to gain perspectives on the above issues. 
Carer policy documents were collected from the 26 Medicare carers to whom sample bene
ficiar claims were submitted to determine their coverage policies relating to TENS. Lastly, 
48 State Medicaid programs and the Veteras Admnistrtion provided information regarding 
their reimbursement of TENS.  FINDINGS

One-third Of The Claims For Beneficiaries Contacted Were Inappropriately Reimbursed 
Medicar carers should not have paid for 33 percent (41 of 126) of the TENS because they 
were either possibly frudulent or they failed to meet the Medicare coverage requirments for 
estimated loss of $4 394 500 to Medicar. 
a tral period, resulting in an 
Nine percent of claims for the beneficiaries contacted are possibly  Eleven 
fraudulent. 
beneficiares denied ever having a TENS. Many added they did not know what a TENS 
was and certnly had never tred one. These questionable claims, representing seven 
suppliers nationwide, include both rentals and purchases. Almost all had what appeared 
to be appropriate signatues and necessar authorization form. (These cases have been 
referred to the OIG' s Office of Investigations. 
Twenty-four percent of the beneficiaries contacted did not have the required trial period 
of at least 1 month. 
 The MCM requirment for a tral period (MCM Section 30-46) was 
not met in 30 cases. Typically, in many of these cases, after a TENS had been 
recommended, a supplier representative would bring the device to the patient s home so 
the patient could tr it; a purchase would then immediately tae place without the 
required tral period. One beneficiar was surprised when the TENS arved because 
afd 
she had never even hear of it, was never shown how to use it and was  to tr it. 
Eight of the 30 beneficiares retued their TENS to the supplier in spite of the fact that 
Medicar had reimbursed for it and thus it belonged to them. 
Carrer procedures to  Based on analysis of the 
enforce trial period need strengthening. 
quaners of the supportng 
85 purchase claims, the following was noted: although the-
documentation mentioned a  had any information to 
tral period, only half of those 
suppon the fact that a successful tral period had taken place. A review of the carers 
policies and procedures indicated that they all did require such documentation but 
apparntly did not enforce this requirment on an ongoing basis. Some carers appear 
to routinely reimburse for the purchase of a TENS after a month' s rental without 
requirg any funher information. An additional carer review weakess is revealed by 
the fact that 39 percent of the authorization forms were dated after the date of delivery. 
(OBRA 1987 prohibits payment unless the supplier receives a wrtten order prior to the 
delivery of the device to the patient. 
More education of medical community about  Only half of the physicians 
TENS needed. 
contacted were awar of TENS guidelines. In addition only half of the Medicare 
carers had sent educational information about TENS coverage to physicians and 
suppliers.  State Medicaid agencies are 
Other payors take diferent approach in approving TENS. 

not required to cover TENS but the majority do. Almost all require prior approval, 
meang that a claim must be submitted with documentation of need and effectiveness 
prior to reimbursement. A few States requir that only physicians in cenain specialties 
can authori TENS. Some States require documentation of patient evaluation durng 
the tral period before the purhase is to be considered. This may include a descrption 
of the patient s emotional status and capacity to use a TENS effectively. Some States 
requi a 
specifc TENS form including questions relating to diagnosis, date of onset, 
durtion of medical necessity, treatment plan, and prognosis. 
The Veteran s Admistration (VA) also uses a prior approval system and requirs evalu
ation durg a tral period with follow-up visits by a clinician after the device is pro
cured. The TENS are obtained from contracted suppliers who deal directly with the VA 
rather than with the patient. pevices are retued to the VA when they are no longer use
ful and are refurbished if cost effective. 
Most Purchased Tens Units Found Helpful; Trial Period Plays Major Role In Assuring 
Appropriate Use 
j really enjoy the relief it gives me because j lived with the agony of back pain for 
so many years. " (a TENS patient) 
of beneficiaries who purchased TENS found it beneficial. 
Nearly 80 percent  (67  of  85) 
The majority had low-back pain and/or anhrtis and had experienced pain for a number 
of year. Most had taken pai medication with varng results. The duration and 
frquency of their use difered considerably from leaving it on all day to using it for a 
few miutes several ties a day. Most used four electrodes and placed them wherever 
they had pai. Some used the TENS on diferent pan of the body at different times, 
dependig on where their pain was. Many said that they moved the electrodes a bit each 
tie they applied them, a practice which clinicians say is advisable to prevent skin 
irtation. Most also changed the intensity to a point where it was helpful; some said 
that point vared dependig on the battery strength. Some (9 of 85) had actually used it 
successfully for acute post-surgical pain, but continued its use for chronic pain. 
Greater role of medical professionals with TENS helps to assure most appropriate use. 
Eighty-four percent (58 of 69) of beneficiares who had their TENS recommended by a 
medical practitioner found it helpful, while only 56 percent (9 of 16) of those who did 
not have it so recommended found it helpful. The remaining 16 beneficiares became 
awar of the TENS from TV ads, senior citizens centers, frends, 
or relatives. 
Only one-third of the patients reported having follow-up care with their medical 
practitioner.  Although there ar no Medicare guidelines requirng follow-up for users 
of TENS, many clinicians contacted encouraged it to ensure the most wonhwhile use of 
the device. They believe that following up to ascertn whether the TENS is working  properly and continuing to relieve pai  The data indicate that 
serves a positive role. 
follow-up does not take place in the majority of cases. However, 17 percent of those 
fid 
beneficiares that did not  TENS helpful had follow-up after purchase; in contrast, 
39 percent of those helped by TENS had such follow-up which suppons the helpfulness 
of keeping in touch with the patient even after the 
tral period. 
Use of the required trial period is critically important in assuring the most effective use 
Of the 85 beneficiares who purchased a TENS, 55 had the benefit of a tral 
of TENS. 

period. Our analysis reveals that virally all of these beneficiares with a tral period 
(53 of 55) found the TENS helpful. In contrst, only 47 percent of those who purchased 
without a tral period (14 of 30) were benefitted. Clinicians also agred that 
a tral 
period that teaches the patient how to best apply and operate the TENS and allows 
evaluation of the device s usefulness is essential. Although clinicians suggest tring
several different units for best results, almost all beneficiares only tred one. 
Beneficiaries Eighty percent of those 
' rental experience supports value of trial period. 
who rented but did not purchase the TENS (24 of 30) found it was not helpful durng 
the 1 month' s tral period and returned it to the supplier. These 24 beneficiares were 
thus given the opportnity to tr the TENS before the clinician reached a decision as to 
its purchase. By determning that it was not helpful, the tral period served to avoid 
inappropriate reimbursement of the TENS. 
Within this group of 30 bebeficiares who rented but did not eventually purchase, 6 expe
rienced some pain relief whie using the TENS. However, they decided not to purchase 
the TENS after their tral period (1 month rental) for a varety of reasons. One individ
ual died, one had the TENS picked up by the supplier, two no longer experienced pain 
and two simply disliked using the device. Of the 30 beneficiares who only rented a 
TENS, almost all had the device explaied to them and also received wrtten instrc
tions on its use. 
Most of the 26 physicians contacted felt very 
Physicians view TENS favorably. 

positively about TENS. A tyical comment was: "TENS units ar effective if used 
properly." This was echoed by many who thought TENS to be an effective tratment 
for selected patients and preferable to prescribing drgs. Two-thirds of the physicians 
said it was their idea to prescribe a TENS and almost all denied any pressure from 
patients, famlies or suppliers to prescribe one. Sixty-five percent (17 of 26) of the 
physicians said the TENS was helpful in relieving pain for the patient in the sample, 
Although the majority of physicians had an ongoing relationship with the patient, one 
quaner saw the patient only when the TENS was ordered. Most (58 percent) said the 
patient was seen durng the tral period by either themselves or a physical therapist to 
the TENS for-ts effectiveness and teach the patient to use it.  Severa physicians suggested that TENS prescrbing be limited to cenain specialists 
with expertse in the area. Other physicians mentioned that they refer their patients who 
are candidates for a TENS to a physical therapist to evaluate the device for its effective
ness and wil wrte a prescrption only if there is a positive result.  RECOMMENDATIONS

The following recommendations were presented to HCFA in the draft repott. To reduce inap
propriate payments for TENS, HCFA should: 
Evaluate And Strengthen, As Needed, Carrier Implementation Of Medicare And Obra 1987 
Requirements To: 
Ensure a tral period prior to purchasing TENS by assurng that a cenification form is 
submitted by the physician which indicates the training of the patient in the use of the 
device and a certfication of its effectiveness for the patient s pain relief. 
Prhibit payment unless the supplier receives a wrtten order from the physician prior to 
the delivery of the device to the patient 
Medicar Carers Manual Transmittal 1284, effective for services ren
HCFA Comments: 

dered on or after Januar 1, 1989, requires that suppliers have a wrtten physician s order in 
hand prior to delivery of a TENS device to a Medicare patient. If the wrtten order is not in 
the supplier s hand prior to delivery, payment may never be made for that item even if a wrt
ten order is subsequently furished by a physician. The item, however, may be provided by 
another supplier to the same patient and, if the appropriate 
requirments are met, payment 
progr. 
may be made under the 
A drt transmittal which includes a new TENS physician certfication form is also in HCFA' 
clearce proess. The new form contains questions regarding patient training, 
tratment, and 
expected improvement with a TENS. This certfication, requird for every beneficiar pur
chase order for a TENS, wil show the results of his/her tral period. 
Publicize Mediare Coverage Requirements To The Medical Community. 
HCFA Comments: 
 Medicare Carers Manual Transmittal 1299, released in April 1989, re
quis 
each carer to notify the State medical society and any applicable specialty societies of 
the medical guidelines to be used in adjudicatiftg TENS claims. 
Add Tens To The MCM Section 7512E Postpayinent Alert List Which Suggests Areas Of De
tectedAbuse That Should Be Considered When Selecting 
Cases For The Current Year 
payment Re  ew. 
Medicar Carers Manual Transmittal 1299 (mentioned above) goes be
HCFA Comments: 

yond the OIG recommendation that TENS be considered during p Car
ostpayment reviews. 
ers are now required to manually review each TENS claim on a prepayment basis. We believe 
that a 100 percent prepayment review of TENS claims is more effective than a postpayment re view conducted on a sample basis. Carers, however, ar not precluded from conducting 
postpayment reviews. They may conduct postpayment reviews of TENS claims to identify 
the existence of program abuse or fraudulent situations.  APPENDIX I

METHODOLOGY 
The data for this inspection was pulled from the 1986 BMA data and represents a 0.4 per
cent sample of al records for that year for whom TENS claims were paid. There were 310 re
cords found representing 210 beneficiares. Accordig to the analysis, 41 of these individuals 
had inappropriate payments totaling $17,578 in allowed charges. This is an average of $83. 
per sample beneficiar (stadard error  69). The total number of beneficiares in 1986 
of 13.
with bils for TENS is estimated to be 52 500. Based on this universe, it is estimated that 
(stada 
there were $4 394 500  error of $718,725) in inappropriate allowed payments in 
1986. The 90 percent confdence interval of this estimate has a lower cutoff point of 
$3,212 197 and an upper cutoff point of $5,576,803. The overal precision of this estiate is 
26.9 percent
Cost savings can also be projected more conservatively based on the 26 beneficiares who ei
ther did not receive the TENS or did not have a tral period and also did not benefit from the 
TENS. These 26 beneficiares had overpayments totaling $10,743 in allowed charges. This is 
an average df$51.16 per sample beneficiar (stadard error of 10. 868). Cost savings is esti
mated to be $2,685,750 (standard error of $570,570) in 1986. The 90 percent confidence inter
val of this estiate has a lower cutoff point of $1,747, 162 and a upper cutoff point of 
$3,624 338. The overal precision of this estimate is 34.9 percent.  APPENDIX II 
The HCFA' s comments on our specific recommendations are included in the repon 
recommedations section. The HCFA's general comments and our responses follow. 
HCFA GENERAL COMMENTS 
We do not agree with the OIG' s finding that "one-third of the claims for beneficiares con
tacted were inappropriately reimbursed. " This finding was based on 11 claims of suspected 
frud 
(the beneficiares denied receipt of a TENS device) and 30 claims where beneficiares re
poned that they had no tral period. Improved claims processing requirements would not have 
resulted in the denial of the potentially fraudulent claims found by the OIG. Therefore, these 
claims should not be included in the methodology for computing the overpayment. Also, pay
ment for the purchase of TENS units without a tral period is not necessarly indicative of an 
progr 
overpayment or unnecessar  reimbursement. A great percentage of these devices 
would have been purchased had a tral period been given. Therefore, the existence of inappro
priate reimburement has not been demonstrted. Based on the above comments regardig the 
OIG' s fmdings, we do not agre that over $4 millon in appropriate payments were made in 
1986. 
Furer
, we are unable to reconcile the statistic;s quoted in paragraph 3, page ii in the Execu
Summ, 
tive  with similar data in the last two paragrphs of thIs same page. Pargraph 3 
states that thee-fours of the 85 beneficiares receiving a TENS had a tral period, and of 
these beneficiares one-hal had a successful tral period. These numbers disagree with the 
last paragrph which states that 53 beneficiares having a tral period "found the TENS help
ful. " Ths dierence should either be explained or the third paragrph changed to coincide 
with the data in the last paragrph. 
OIG RESPONSE 
We respond to HCFA's genera comments concerning the issue of reimbursement and statisti': 
cal discrepancies in the following manner: 
HCFA defines inappropriate reimbursement differently than we do. We believe that all 
payments that are not allowable under law or regulations are inappropriate whether or 
not contrctors are able to identify the problems. Therefore we continue to suppon 
finding number one. In the 11 instances where the beneficiares denied receipt of the 
TENS, the clais were inappropriately reimbursed. 
Relative to the 30 beneficiares who did not have.a tral period, Medicar coverage 
guidelines requie that, when used for the tratment of chronic intractable pain, TENS is 
used by the patient on a  and its effectiveness is monitored by the physician or 
tral basis 
physical therapist This is an importt safeguard for preventing inappropriate reimbur sement of the TENS. If a TENS unit is purchased without the required tral period and 
helpful, the usefulness of the TENS is incidental to the 
the beneficiar finds the device 
fact that the carer should not have paid for it without determning that it had been tred 
and was found helpful in alleviating pain. 
The statistics quoted in paragraph 3 of page ii in the Executive Summar were derived 
frm information provided from the supportng documentation submitted with the 85 
sample purchase claims. The figures used in the last paragrph of the same page, 
however, were derived from actual interviews with the beneficiares themselves. 
Therefore, the diference in figurs can be explained by the source of data used.