Abstract
Background:
Antenatal care is an important health service which detects and sometimes reduces the risk of complications among pregnant women. The quality of care is likely to influence effective utilization and compliance with interventions.
Objectives:
This study evaluated clients’ perception of antenatal care quality at the University College Hospital (UCH), Ibadan and determined levels of client satisfaction.
Methods:
Women presenting for antenatal care at the study centre were interviewed in a cross-sectional design using a structured questionnaire. Items in the questionnaire included sociodemographic and obstetric variables, assessment of quality of amenities, waiting time and level of satisfaction. Data analysis was done using frequency tables, Chi-square cross tabulations and logistic regression. The p-value was set at P<0.05.
Results:
There were 239 participants; 74% percent of the women were aged 25-34 years; majority of the respondents (86%) had tertiary education while 49.4% were skilled workers or professionals. In 57.7% of women, the gestational age was between 13 and 27 weeks while 66.1% were Para 1-4. Amenities and water supply were regarded as unsatisfactory in 60.7% and 61.9% respectively. The clinic services were regarded as good in 81.1% of respondents; the only significant association with patient satisfaction was the desire to register in the same facility in the next pregnancy.
Conclusion:
There is a high overall level of satisfaction with antenatal services among pregnant women in UCH. Policy makers and health providers should however address improvement of amenities, reduction of waiting time and ensure that health interventions are available for all clients.
Keywords: Antenatal care, Perception, Satisfaction, Ibadan, Pregnancy.
INTRODUCTION:
Antenatal care (ANC) is an important part of preventive medicine and professionals providing this service can reduce the risk of complications through education, counseling and various interventions. The proportion of Nigerian women that receive antenatal care and those that are delivered by skilled birth attendants has however remained far from acceptable1.
For many years, high standards of care were considered a luxury particularly in developing countries where service coverage was largely inadequate 2, 3. Quality of health care is seen as a factor closely related to effectiveness, compliance and continuity of care particularly for ethical reasons4. Women’s perceptions of antenatal visits significantly influence their assessment of quality of services that are provided5. As a result of this new focus, measurement of customer satisfaction has become equally important in assessing system performance.
Patient satisfaction has traditionally been linked to the quality of services given and the extent to which specific needs are met. Satisfied patients are likely to come back for the services and recommend services to others6. Various factors including attitude of staff, cost of care, time spent at the hospital and doctor communication have been found to influence patient satisfaction in previous studies7-9. The study objective was to ascertain the perception of and satisfaction with the quality of ANC services among pregnant women at the UCH, Ibadan. The study also sought to correlate patient’s satisfaction with future use of maternity services in the institution.
MATERIALS AND METHODS
This cross sectional study was conducted at the antenatal clinic of the UCH, Ibadan, a tertiary institution in South-Western Nigeria. In 2009, clinic attendance was 13,932 (daily average of 82 women) and 8,811(daily average of 55 women) in 2010. There are three antenatal clinics per week, 1 booking and postnatal clinic on Wednesday and Friday respectively. The clinic usually commences with an interactive health talk co-ordinated by a qualified community health nurse which usually lasts for at least 45minutes.
The health talk usually covers various topical issues including nutrition, diet, personal hygiene, danger signs in pregnancy, the labour experience, care of the newborn, exclusive breast feeding and immunization.
Other health issues such as hypertension, diabetes mellitus, malaria, anaemia, HIV/AIDS and family planning are also discussed. Routine services following the health talk include weight and height measurement, blood pressure estimation, urinalysis, haemoglobin estimation and multivitamin supplementation. Thereafter, patients are called individually to see their doctors for clinical examination and treatment.
In this study, study participants were selected by convenience sampling following their written consent. Women attending booking and post-natal clinics were excluded. The instrument for the study was an interviewer administered questionnaire which was divided into sections: Socio-demographic and obstetric characteristics, Ser vices/procedures, Amenities, Content of health information & education, Cost implication, Attitude of health personnel, Waiting time/total time spent, Effective communication and Overall rating of antenatal care services. Each questionnaire took 10-15 minutes to complete. Total time spent was defined as time spent from arrival to the end of the clinic consultation by the obstetrician waiting time was defined as time spent from the end of the health talk to the beginning of the clinic consultation; these values were obtained from the patient. The interviewers were research assistants who were trained to administer the questionnaire in English language. Translation to native languages was done in cases where the respondents were uneducated. The questions were closed and open ended and written in simple language. Sample size calculation was done using the Kish formula for cross sectional studies; an overall client satisfaction prevalence of 81% with a precision of 0.05 was used 10.
The data was collected, coded and entered into a computer using SPSS v.15.0. The data was then cleaned and analysis carried out using descriptive statistics and frequency tables. Cross tabulation was done between socio-demographic variables and client satisfaction and significant variables were entered into a logistic regression model to identify predictors. The level of significance was <0.05.
RESULTS
There were 239 respondents and most of them were between 25 and 29 years old (37.2%); 36.8% were in the 30-34years age group. Most of the women were married (94.6%) and in monogamous unions. There were 187(78.2%) Yoruba women while 86% had tertiary education. Skilled workers or professionals accounted for 49.4% of respondents while 82% lived in urban areas (Table 1).
Table 1.
Socio-demographic characteristics of respondents
| Characteristic | Frequency (n) | Percentage (%) |
|---|---|---|
| Age | ||
| 20-24 | 24 | 10.1 |
| 25-29 | 89 | 37.2 |
| 30-34 | 88 | 36.8 |
| ≥35 | 38 | 15.9 |
| Total | 239 | 100 |
| Marital status | ||
| Single | 13 | 5.4 |
| Married | 226 | 94.6 |
| Total | 239 | 100 |
| Occupation | ||
| Unemployed | 57 | 23.8 |
| Unskilled | 16 | 6.7 |
| Semi-skilled | 48 | 20.1 |
| Skilled/Professionals | 118 | 49.4 |
| Total | 239 | 100 |
| Education | ||
| None | 1 | 0.4 |
| Primary | 5 | 2.1 |
| Secondary | 28 | 11.7 |
| Post- secondary | 205 | 85.8 |
| Total | 239 | 100 |
| Ethnicity | ||
| Yoruba | 187 | 78.2 |
| Ibo | 34 | 14.2 |
| Hausa | 9 | 3.8 |
| Others | 9 | 3.8 |
| Total | 239 | 100 |
Majority of the respondents (57.7%) were between 13 and 27 weeks of gestation while 26.8 % (64) were less than or equal to 12 weeks; gestational age was 28 weeks and above in 15.5% (37). Sixty five respondents were nulliparous (27.2%) while majority were Para 1- 4(66.1%); in 16 women (6.7%), parity was >5 (Table 1).
The commonest investigation/procedure done at the clinic was packed cell volume (PCV) estimation (99.2%). Human immunodeficiency virus (HIV) screening was done in 77% of respondents. Sitting arrangements were regarded as satisfactory in 97.9% of women. Toilet, bathroom facilities and water supply were regarded as unsatisfactory in 60.7% and 61.9% respectively. Two hundred and nineteen (91.6%) of respondents reported that diet and nutrition related topics were more discussed during the interactive session than other topics. However, prevention of cervical cancer was the least discussed topic (65.7%) (Tables 2&3). The perception of attitude of health care providers is highlighted in table 5. One hundred and thirty seven respondents (85.6%) rated the attitude of nurses at the clinic as good and were satisfied with the antenatal services. Conversely, of the 79 respondents who rated the nurses’ attitude as poor, 57(72.2%) were satisfied with the antenatal care service which was significant (p<0.05). A hundred and ninety respondents(84.4%) who expressed satisfaction with ANC services described the doctor’s attitude towards them as good while 57.1% of them who had a contrary opinion of the attitude of doctors were still satisfied with ANC; this was also significant(p<0.05). The mean time spent during each clinic visit was 3.8±1.5hours (range: 1-7hours). About 94.9% of respondents who spent within 3hours at the clinic expressed satisfaction while 35.1% of respondents who thought they spent too long at the antenatal clinic were dissatisfied (p<0.05) (table 5).
Table 2.
Services provided at antenatal facility
| Service Provided n=239 | Yes N (%) | No N (%) |
|---|---|---|
| Registration | 234(97.9) | 5(2.1) |
| Blood Pressure | 235(98.3) | 4(1.7) |
| Height | 232(97.1) | 7(2.9) |
| Urine Test | 236(98.7) | 3(1.3) |
| Packed Cell Volume | 237(99.2) | 2(0.8) |
| Blood Group | 228(95.4) | 11(4.6) |
| Haemoglobin Genotype | 218(91.2) | 21(8.8) |
| VDRL | 200(83.7) | 39(16.3) |
| Retroviral Screening | 184(77.0) | 55(23) |
| Tetanus | 188(78.7) | 51(21.3) |
| Malaria | 205(85.8) | 34(14.2) |
| Iron and Folic Acid Tablet | 187(78.2) | 52(21.8) |
| Ultrasound Scan | 194(81.2) | 45(18.8) |
| Physical Examination | 214(89.5) | 25(10.5) |
| Appointment for next visit | 220(92.1) | 19(7.9) |
Table 3.
Assessment of amenities and health topics discussed at facility
| Amenities (n=239) | Satisfied(n/%) | Not satisfied(n/%) |
|---|---|---|
| Water supply | 148(61.9) | 91(38.1) |
| Hygiene(toilet & bathroom) | 145(60.7) | 94(39.3) |
| Electricity supplys | 189(79.1) | 50(20.9) |
| Ventilation | 201(84.1) | 38(15.9) |
| Sitting arrangement & spacing | 234(97.5) | 5(2.5) |
| General environmental sanitation | 227(95.0) | 12(5.0) |
| Health information & Education | 224(93.7) | 15(6.3) |
| Health topics(n=239) | Yes(n/%) | No(n/%) |
| Diet & Nutrition | 219(91.6) | 20(8.4) |
| Danger signs of pregnancy | 203(84.9) | 36(15.1) |
| Child care and breast feeding | 211(88.3) | 28(11.7) |
| Family planning and child spacing | 168(70.3) | 71(29.7) |
| Prevention of malaria in pregnancy | 211(88.3) | 28(11.7) |
| Prevention of sexually transmitted infections | 194(81.2) | 45(18.8) |
| HIV/AIDS information & counselling | 217(90.8) | 22(9.2) |
| Prevention of cervical cancer | 157(65.7) | 82(34.3) |
| Breast self-examination | 168(70.3) | 71(29.7) |
Table 5.
Cross tabulation of overall rating of antenatal services and socio-demographic variables
| Evaluation of ANC | Not satisfied n (%) | Satisfied n(%) | Significance |
|---|---|---|---|
| Health information | |||
| Yes | 42(17.9) | 193(82.1) | p>0.05 |
| No | 1(25.0) | 3(75.0) | |
| Time taken to see doctor | |||
| <3hrs | 25(15.4) | 137(84.6) | p>0.05 |
| >3hrs | 19(24.7) | 58(75.3) | |
| Total time spent at ANC | |||
| <3hrs | 3(5.1) | 56(94.9) | p<0.05 |
| >3hrs | 15(14.6) | 88(85.4) | |
| Too long | 27(35.1) | 50(64.9) | |
| Nurses’ attitude | |||
| Poor | 22(27.8) | 57(72.2) | p<0.05 |
| Good | 23(14.4) | 137(85.6) | |
| Doctors’ attitude | |||
| Poor | 6(42.9) | 8(57.1) | p<0.05 |
| Good | 35(15.6) | 190(84.4) | |
| Paid for ANC | |||
| Yes | 37(19.0) | 158(81.0) | p>0.05 |
| No | 7(15.9) | 37(84.1) | |
| Cost of registration | |||
| Expensive | 31(15.6) | 168(84.4) | p>0.05 |
| Not expensive | 10(25.0) | 30(75.0) | |
| Cost of other ANC services | |||
| Expensive | 23(16.5) | 116(83.5) | p>0.05 |
| Not expensive | 17(17.0) | 83(83.0) | |
| Register at facility again | |||
| No | 13(52) | 12(48) | p<0.05 |
| Yes | 41(19.2) | 173(80.8) | |
| Recommend facility to somebody else | |||
| No | 6(54.5) | 5(45.5) | p<0.05 |
| Yes | 38(16.7) | 190(83.3) | |
The overall rating was classified into poor and good. Most respondents were satisfied with the services given at the clinic; 81.1% rated the services as good while 18.9% were not satisfied and stated that service was poor. Most women (83.3%) revealed that they would register in the same health facility in subsequent pregnancies and would recommend the clinic to someone else. Following cross tabulation with the ÷square test(tables 4&5), only total time spent, nurses’ attitude, doctors’ attitude, desire to register again at the facility and deciding to recommend the facility to someone else were significant. These were entered into the logistic regression model. (Table 6). The only significant association was between desire to register in the facility in a future pregnancy and satisfaction (p<0.05).
Table 4.
Determinants of patients’ satisfaction (Overall Rating)
| Sociodemographic/Obstetric variables | Not satisfied n(%) | Satisfied n(%) | Significance |
|---|---|---|---|
| Age | |||
| 20-24 | 3(12.5) | 21(87.5) | p>0.05 |
| 25-29 | 21(23.6) | 68(76.4) | |
| 30-34 | 25(28.4) | 63(71.6) | |
| ≥35 | 6(18.8) | 32(81.2) | |
| Marital Status | |||
| Single | 5(38.5) | 8(61.5) | p>0.05 |
| Married | 41(18.1) | 185(81.9) | |
| Parity | |||
| Nulliparous | 8(12.3) | 57(87.7) | p>0.05 |
| Para 1-4 | 18(11.4) | 140(88.6) | |
| Para ≥5 | 2(12.5) | 14(87.5) | |
| Gestational Age(wks) | |||
| <12 | 19(29.7) | 45(70.3) | p>0.05 |
| 13-27 | 28(20.3) | 110(79.7) | |
| ≥28 | 7(18.9) | 30(81.1) | |
| Occupation | |||
| Unemployed | 9(15.8) | 48(84.2) | p>0.05 |
| Unskilled | 5(33.3) | 10(66.7) | |
| Semi-skilled | 7(15.9) | 37(84.1) | |
| Skilled/Professionals | 4(3.5) | 109(96.5) | |
| Education | |||
| Secondary and below | 2(8.8) | 31(91.2) | p>0.05 |
| Post-secondary | 42(20.5) | 163(79.5) | |
| Socio-economic class | |||
| Lower | 3(12.7) | 55(87.3) | p>0.05 |
| Upper | 35(19.4) | 145(80.6) | |
| Place of residence | |||
| Urban | 43(20.9) | 163(79.1) | p>0.05 |
| Rural | 9(27.3) | 24(72.7) | |
| Distance from ANC | |||
| Close | 11(15.9) | 58(84.1) | p>0.05 |
| Far | 11(15.1) | 62(84.9) | |
Table 6.
Logistic regression analysis - predictor variables of client satisfaction
| Variable | OR (CI) | P |
|---|---|---|
| Time | ||
| Less than 3hrs (ref) | ||
| More than 3hrs | 0.73(0.03-16.79) | 0.84 |
| Too long | 0.19(0.01-2.96) | 0.23 |
| Doctors’ attitude | ||
| Poor (ref) | ||
| Good | 0.50(0.04-6.30) | 0.59 |
| Nurses’ attitude | ||
| Poor (ref) | ||
| Good | 4.58(0.78-27.05) | 0.09 |
| Register again in the facility | ||
| No (ref) | ||
| Yes | 36.50(3.89-341.65) | 0.00 |
| Recommend the facility | ||
| No (ref) | ||
| Yes | 4.22(0.33-53.76) | 0.27 |
DISCUSSION
Our study evaluated the perception of patients and their level of satisfaction with antenatal care. Previous research has revealed positive correlation between patients’ satisfaction and health care utilization10, 11. Majority of the women were satisfied with the quality of antenatal care they received and would recommend the facility to friends. The participants were also willing to use the same facility in subsequent pregnancies. It was however observed that the level of satisfaction was not always in tandem with willingness to access the services. An earlier survey suggested that women may generally express satisfaction with the quality of antenatal services despite inconsistencies between received care and their expectations of the facilities10. Other authors have stated that client satisfaction may only indicate low expectations from health care services or a desire to please the interviewer, avoid anxieties about provider bias or express feelings driven by cultural perceptions12, 13. Oladapo and Osiberu found that socio-demographic and obstetric characteristics were not associated with the overall satisfaction with antenatal care quality14. There was a similar finding in this study as they are seen to have limited impact on their perception of antenatal care.
Specifically, a significant proportion of clients viewed waiting time as long. This is similar to findings from Kano in Northern Nigeria15. Another study demonstrated that customer satisfaction is affected not just by waiting time but by customer expectations or attribution of causes for waiting. 16. Consequently, one of the issues in queue management is not only the actual amount of time the customer has to wait but also the customer’s perceptions of that wait 17. The views of the clients’ about waiting time may be related to the hospital’s location in the most populous part of the state with numerous referrals from different levels of care.
The high level of satisfaction with the cost of antenatal care obtained in this study may have resulted from the safety net provided to some respondents by the National Health Insurance Scheme (NHIS), waivers for staff of the UCH and for People Living with HIV/AIDS (PLWHA). In spite of this, a good number of patients who paid for their antenatal care which they mostly perceived as expensive still expressed satisfaction. Clients may be willing to accept higher costs if they believe that services are of high quality. This has been observed in Indonesia where clients were willing to pay reasonable fees for quality antenatal and post-natal care; other research has found that ill and poor people by passed free or subsidized services in facilities they perceived to be offering low quality18.
The attitude of health personnel was a significant determinant of patients’ perception and satisfaction with antenatal care in this study; this was a similar pattern in some studies and a contrast with others15, 19, 20. Good provider-patient relationships are therapeutic and have been described as the single most important component of good medical practice, not only because it identifies problems quickly and clearly, but it also defines expectation and helps establish trust between the clinician and patient 21, 22. Supervision of antenatal care and the contributions of ancillary bodies such as SERVICOM may have played a role in the patient’s perception of the health personnel’s attitude. The availability and level of utilization of such services was observed to be higher than other similar studies in this environment.11, 23, 24. This may be attributable to a recent upgrade of facilities at the clinic by the hospital management. The perception of patients to HIV screening might be associated with understanding of the counseling process as HIV screening is established as a mandatory test in the study centre. An unfortunate finding was the relatively infrequent discussion of cervical cancer prevention during antenatal clinic sessions; cervical cancer remains a significant cause of mortality among women in developing countries and this needs to be urgently addressed by policy makers. Our study included women irrespective of the number of antenatal clinic visits; this may limit interpretation because some women may not have had enough exposure to the clinic to enable them make concrete judgments on perception and satisfaction. Other possible influences on our study outcomes include selection of subjects without randomization and recall bias. Findings from the logistic regression confirm that continued utilization of antenatal services is directly linked to the satisfaction of the clients. This reemphasizes the need for continued audit and evaluation of services at the antenatal clinic by health providers and policy makers.
CONCLUSION
In conclusion, among pregnant women receiving prenatal care at the Antenatal Clinic, UCH, Ibadan, levels of satisfaction were high. Most respondents were willing to recommend antenatal care at this facility to relatives and friends. Periodic feedback from clients by policy makers and hospital managers should be instituted as part of antenatal care evaluation. Larger prospective studies and focus group interviews may provide more information on what women think about antenatal care services and changes that they would expect in their health facility.
REFERENCES
- 1.UNFPA Nigeria. Nigeria Demographic and Health Survey 2008, http://www/nigeria.unfpa.org/pdf/nigeriadhs2008.pdf . [accessed 1 May 2013].
- 2.Chakraborty N, et al. Determinants of the use of maternal health services in rural Bangladesh. Health Promot Int. 2003;18:327–336. doi: 10.1093/heapro/dag414. [DOI] [PubMed] [Google Scholar]
- 3.Mensch B. Quality of care: a neglected dimension. In: Koblinsky M, Timyan J, Gay J, Boulder J, et al., editors. The Health of Women: A Global Perspective. San Francisco & Oxford: West View Press; 1993. pp. 235–253. [Google Scholar]
- 4.Asadi-Lari M, et al. Patients’ needs, satisfaction, and health related quality of life: Towards a comprehensive model. Health Qual Life Outcomes. 2004;2:32. doi: 10.1186/1477-7525-2-32. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Kamil A, Khorshid E. Maternal perceptions of antenatal care provision at a tertiary level hospital, Riyadh. Oman Med J. 2013;28(1 ):33–35. doi: 10.5001/omj.2013.07. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Zaky HH, et al. Assessing the quality of reproductive health services in Egypt via exit interviews. Matern Child Health J. 2007;11(3 ):301–306. doi: 10.1007/s10995-006-0167-y. [DOI] [PubMed] [Google Scholar]
- 7.Ofovwe CE, Ofili AN. Indices of patient satisfaction in an African population. Public Health. 2005;119(7 ):582–586. doi: 10.1016/j.puhe.2004.10.012. [DOI] [PubMed] [Google Scholar]
- 8.Al-Doghaither AH, Abdelrhman BM, Saeed AA. Patients’ satisfaction with physicians’ services in primary healthcare centers in Kuwait City, Kuwait. J R Soc Promot Health. 2000;120(3 ):170–174. doi: 10.1177/146642400012000306. [DOI] [PubMed] [Google Scholar]
- 9.Donabedian A. The definition of quality and approaches to its assessment. Ann Arbor, Michigan: Health administration press; 1980. pp. 79–128. [Google Scholar]
- 10.Oladapo OT, et al. Quality of antenatal services at the primary care level in Southwest Nigeria. Afr J Reprod Health. 2008;12(3 ):71–92. [PubMed] [Google Scholar]
- 11.Deccacche A. Evaluating quality and effectiveness in the promotion of health: approaches and methods of public health and social sciences. Promotion and education. 1997. [DOI] [PubMed]
- 12.Creel LC, Sass JV, Yinger NV. New Perspectives on Quality of Care: No. 2, Population Reference Bureau, http://www.prb.org/pdf/ NewPerspQOC-Clients.pdf . 2002.
- 13.Grigoryan R. Investigating reasons for high patient satisfaction given low utilization of health care services, Armenia . Qualitative Research, http://auachsr.com/PDF/MPH/2007/ GrigoryanRuzanna.pdf . 2007.
- 14.Oladapo OT, et al. Do socio-demographic characteristics of pregnant women determine their perception of antenatal care quality. Matern Child Health J. 2009;13(4 ):505–511. doi: 10.1007/s10995-008-0389-2. [DOI] [PubMed] [Google Scholar]
- 15.Iliyasu Z, et al. Patients’ satisfaction with services obtained from Aminu Kano Teaching Hospital, Kano, Northern Nigeria. Niger J Clin Pract. 2010;13(4 ):371–378. [PubMed] [Google Scholar]
- 16.Taylor S. Waiting for Service: The Relationship between Delays and Evaluation of Service. Journal of Marketing. 1994;58(2 ):56–69. [Google Scholar]
- 17.Davis MM, et al. How Disconfirmation, Perception and Actual Waiting Times Impact. Unpublished Manuscript. 1998.
- 18.Akin JS, Hutchinson P. Health-care facility choice and the phenomenon of by-passing. Health Policy Plan. 1999;14:135–151. doi: 10.1093/heapol/14.2.135. [DOI] [PubMed] [Google Scholar]
- 19.Adekunle AO, et al. Clients’ perceptions of the Quality of Antenatal Care. J Nat Med Assoc. 2008;100(9 ):1052–1057. doi: 10.1016/s0027-9684(15)31443-7. [DOI] [PubMed] [Google Scholar]
- 20.Olumide EAA, Ajayi IO. Are the patients safe and satisfied?. Conference proceedings at the National conference on PHC; 13th– 16th April 1999; Abuja, Nigeria. pp. 85–96. [Google Scholar]
- 21.Bush T, et al. The impact of physician attitude on patient satisfaction with care of low back pain. Arch. Fam. Med. 1993;2(3 ):301–305. doi: 10.1001/archfami.2.3.301. [DOI] [PubMed] [Google Scholar]
- 22.Wilson P, et al. How perceptions of a simulated physician-patient interaction influence intended satisfaction and compliance. Soc. Sci. Med. 1982;16(19 ):1699–1704. doi: 10.1016/0277-9536(82)90095-8. [DOI] [PubMed] [Google Scholar]
- 23.Osungbade K, Oginni S, Olumide A. Content of antenatal care services in secondary health care facilities in Nigeria: implication for quality of maternal health care. Int J Qual Health care. 2008;20(5 ):346–351. doi: 10.1093/intqhc/mzn026. [DOI] [PubMed] [Google Scholar]
- 24.Balogun OR. Patients perception of quality of antenatal services in four selected private facilities in Ilorin, Kwara State of Nigeria. Nigerian Medical Practitioner. 2007;51(4 ):80–84. [Google Scholar]