Psychometric Properties of the Korean Version of the Inner Strength Questionnaire

Suhyeon Choi; Eunjung Ryu

doi:10.5388/aon.2016.16.1.38

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Choi and Ryu: Psychometric Properties of the Korean Version of the Inner Strength Questionnaire

Original Article

Asian Oncology Nursing 2016; 16(1): 38-45.

Published online: 31 March 2016

DOI: https://doi.org/10.5388/aon.2016.16.1.38

Psychometric Properties of the Korean Version of the Inner Strength Questionnaire

Suhyeon Choi¹, Eunjung Ryu²

¹Department of Nursing, Graduate School of Chung-Ang University, Seoul, Korea.

²Department of Nursing, Chung-Ang University, Seoul, Korea.

Address reprint requests to: Ryu, Eunjung. Department of Nursing, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Korea. Phone: +82-2-820-5681, Fax: +82-2-824-7961, go2ryu@cau.ac.kr

Received 21 January 2016 Revised 26 March 2016 Accepted 27 March 2016

(open-access):

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Purpose

The purpose of this study is to verify the validity and reliability of the the Inner Strength Questionnaire-Korean version (ISQ-K).

Methods

The questionnaire was provided to breast cancer survivors in two Cancer centers in Gyeonggi, Korea and 167 surveys were analyzed. Data were analyzed by CVI for contents validity, confirmative factor analysis for construct validity and correlation for criteria validity. Test-retest analysis and Cronbach's α was calculated for reliability.

Results

Content validity was excellent. Confirmative factor analysis was performed on 4 factors based on the original structures and the goodness-of-fit was as followed: χ² =784.01, df=318, RMSEA=.09, TLI=.78, CFI=.72, GFI=.72. Standard errors of variance ranged from 0.06 to 0.15. Inner strength was correlated positively with resilience (r=.47, p<.001). Test-retest reliability was 0.90 and internal consistency was indicated by Cronbach alphas of 0.85 for inner strength.

Conclusion

We conclude that the ISQ-K would be a valuable tool in evaluating inner strength among breast cancer survivors.

Keywords: Survivors, Breast Neoplasms, Resilience, Quality of Life, Neoplasms

Figures and Tables

Table 1

Sociodemographic Characteristics (N =167)

Characteristics	Categories	n (%) or M±SD	Min	Max
Age (year)		49.1 ± 9.41
	18~29	3 (1.8)	24	29
	30~39	23 (13.8)	32	39
	40~49	60 (35.9)	40	49
	50~59	62 (37.1)	50	59
	60~69	16 (9.6)	60	69
	70~	3 (1.8)	73	80
Marital status	Single	11 (6.6)
	Married	133 (79.6)
	Divorced/separated/widowed	23 (13.8)
Education	Elementary school	5 (3.0)
	Middle school	14 (8.4)
	High school	73 (43.7)
	Above college	75 (44.9)
Job	Housewife	100 (59.9)
	Company employee	19 (11.4)
	Professional	18 (10.8)
	Self-employed	14 (8.4)
	Etc.	16 (9.5)
Religion	None	47 (28.1)
	Christianity	54 (32.3)
	Catholic	26 (15.6)
	Buddhism	29 (17.4)
	Etc.	11 (6.6)
Monthly income (KRW)	> 1,000,000	26 (15.6)
	1~2,000,000	24 (14.4)
	2~3,000,000	31 (18.6)
	3~4,000,000	36 (21.6)
	≥4,000,000	44 (26.3)
	No response	6 (3.5)

SD=Standard deviation; Etc=et cetera; KRW=Korean Won.

Table 2

Clinical Characteristics (N =167)

Characteristics	Categories	n (%) or M ± SD	Min	Max
Time since diagnosis in month		41.7 ± 51.7	0	220
First diagnosis cancer stage	Stage I	43 (25.7)
	Stage II	81 (48.5)
	Stage III	43 (25.7)
Surgery type	Lumpectomy	98 (58.7)
	Mastectomy	51 (30.5)
	Not surgery	18 (10.8)
Chemotherapy	Yes	144 (86.2)
Radiation	Yes	98 (58.7)
Hormone therapy	Yes	94 (56.3)
Clinical process	Chemotherapy	45 (26.9)
	Radiotherapy	2 (1.2)
	Hormone therapy	4 (2.4)
	Chemo + RT	21 (12.6)
	Chemo + Hx	14 (8.4)
	RT + Hx	11 (6.6)
	Chemo + RT + Hx	65 (38.9)
	No treatment	5 (3.0)
Metastasis status	Yes	34 (20.4)
Recurrent status	Yes	9 (5.4)

SD=Standard deviation; RT=Radiotherapy; Hx=Hormone therapy.

Table 3

Correlation Coefficients among the ISQ-K Scores and Factor Scores (N =167)

Variables	ISQ-K	Eng	Conn	Ang	Mov
ISQ-K	1	.71 (<.001)	.63 (<.001)	.60 (<.001)	.53 (<.001)
Eng	-	1	.21 (<.001)	.37 (<.001)	.36 (<.001)
Conn	-	-	1	- .002	.30 (<.001)
Ang	-	-	-	1	- .07
Mov	-	-	-	-	1

ISQ-K: Inner Strength Questionnaire Korean version; Eng=Engagement; Conn=Connectedness; Ang=Anguish and searching; Mov=Movement.

Table 4

Confirmative factor analysis results of ISQ-K (N =167)

Variables			Unstandardized estimate	Standardized estimate	Standardized error	CR	p
Anguish and searching	→	14. I worry about my health.	0.78	.60	.12	6.82	< .001
		15. I am scared about the future.	0.93	.67	.13	7.44	< .001
		16. When I first learned about my health problem, I was afraid of dying.	1.28	.78	.15	8.46	< .001
		17. There are many times when I am afraid of dying.	1.31	.86	.15	9.00	< .001
		18. I feel my situation is out of control.	0.39	.45	.07	5.26	< .001
		19. I dwell on my illness.	0.86	.64	.12	7.15	< .001
		20. When I first learned about my health problem, I felt afraid.	1	.66
Connectedness	→	7. I have at least one person close to me.	0.15	.15	.08	1.84	.065
		8. I feel the presence of God or a Greater Source of Strength.	1.28	.85	.13	9.56	< .001
		9. I put control of my life in God's or a Greater Power's hand.	1.64	.88	.17	9.75	< .001
		10. I feel close to God or a Greater Source of Strength.	1.61	.88	.16	9.80	< .001
		11. I pray for strength.	0.83	.59	.12	6.91	< .001
		12. I express my fears to my God or a Greater Source of Strength.	1.48	.81	.16	9.13	< .001
		13. I pray for others.	1	.66
Engagement	→	1. I tell myself I can do this.	0.89	.72	.10	8.86	< .001
		2. I can change my attitude when I need to.	0.89	.65	.11	8.06	< .001
		3. I believe I am a strong person.	1.26	.82	.13	10.03	< .001
		4. I am determined to get well.	1.09	.76	.12	9.31	< .001
		5. I believe I have inner strength.	1.39	.86	.13	10.59	< .001
		6. I can decide what to do.	1	.72
Movement	→	21. I can live with my physical limitations.	0.36	.24	.13	2.73	.006
		22. I stay active.	0.61	.42	.13	4.66	< .001
		23. I spend time with my friends or family.	0.62	.45	.13	4.98	< .001
		24. I try to balance work and play.	0.92	.69	.13	7.07	< .001
		25. I take time for myself.	0.99	.75	.13	7.46	< .001
		26. I try to rest my mind periodically.	1.07	.80	.14	7.75	< .001
		27. I set aside time to relax.	1	.63

CR=Critical ratio.

Table 5

Reliability of the ISQ-K

Variables	Categories	Total	Ang	Conn	Eng	Mov
Test-retest reliability (n = 12)	Test M ± SD	102.58 (15.31)	20.25 (5.29)	29.50 (5.45)	24.33 (4.05)	28.50 (3.63)
	Retest M ± SD	100.17 (8.02)	21.25 (4.77)	28.92 (4.68)	23.33 (3.03)	26.83 (2.72)
	Pearson correlation (p)	.90 (< .001)	.86 (< .001)	.74 (.006)	.79 (.002)	.41 (.181)
Internal consistency reliability (n = 167)	Chronbach's α	.85	.85	.88	.89	.77
Internal consistency reliability (n = 167)	No. of items	27	7	7	6	7

ISQ-K=Inner strength questionnaire Korean version; SD=Standard deviation; Ang=Anguish and searching; Conn=Connectedness; Eng=Engagement; Mov=Movement.

Notes

This article is based on a part of the first author's master's thesis from Chung-Ang University.

References

1. Korea Center Cancer Registry. 2012 National Cancer Statistics Korea Center Cancer Registry. 2014. Accessed April 18, 2015. http://www.cancer.go.kr/ebook/104/PC/104.html.

2. Hong SK. Concept development of resilience: focusing on cancer patients. J Korean Acad Soc Nurs Educ. 2009; 15(1):109–119.

3. Annunziata MA, Muzzatti B, Giovannini L, Romito F, Cormio C, Mattioli V, et al. Is long-term cancer survivors’ quality of life comparable to that of the general population? An italian study? Support Care Cancer. 2015; 23(9):2663–2668.

4. Costa-Requena G, Rodríguez A, Fernández-Ortega P. Longitudinal assessment of distress and quality of life in the early stages of breast cancer treatment. Scand J Caring Sci. 2013; 27(1):77–83.

5. Knobf MT. Psychosocial responses in breast cancer survivors. Semin Oncol Nurs. 2007; 23(1):71–83.

6. Koch L, Jansen L, Herrmann A, Stegmaier C, Holleczek B, Singer S, et al. Quality of life in long-term breast cancer survivors-a 10-year longitudinal population-based study. Acta Oncol. 2013; 52(6):1119–1128.

7. Stein KD, Syrjala KL, Andrykowski MA. Physical and psychological long-term and late effects of cancer. Cancer. 2008; 112:Suppl 11. 2577–2592.

8. Härtl K, Schennach R, Müller M, Engel J, Reinecker H, Sommer H, et al. Quality of life, anxiety, and oncological factors: a follow-up study of breast cancer patients. Psychosomatics. 2010; 51(2):112–123.

9. Kwon EJ, Yi M. Distress and quality of life in breast cancer survivors in Korea. Asian Oncol Nurs. 2012; 12(4):289–296.

10. Byun HS, Kim GD. Impacts of fatigue, pain, anxiety, and depression on the quality of life in patients with breast cancer. Asian Oncol Nurs. 2012; 12(1):27–34.

11. Hwang E, Yi M. Factors influencing quality of life in patients with breast cancer on hormone therapy. J Korean Acad Nurs. 2014; 44(1):108–117.

12. Norberg M, Magnusson E, Thyme KE, Åström S, Lindh J, Öster I. Breast cancer survivorship-intersecting gendered discourses in a 5-year follow-up study. Health Care Women Int. 2015; 36(5):617–633.

13. Yun MR, Song MS. A qualitative study on breast cancer survivors’ experiences. Perspect Nurs Sci. 2013; 10(1):41–51.

14. Ryu YM, Yi M. The factors influencing quality of life in women with breast cancer. Asian Oncol Nurs. 2013; 13(3):121–127.

15. Roux G, Dingley C. Promoting inner strength. In : Lester JL, Schmitt P, editors. Cancer rehabilitation and survivorship: transdisciplinary approach to personalized care. Pittsburgh, Pennsylvania: Oncology Nursing Society;2011. p. 295–305. .

16. Dingley C, Roux G. The role of inner strength in quality of life and selfmanagement in women survivors of cancer. Res Nurs Health. 2014; 37(1):32–41.

17. Lewis KL, Roux G. Psychometric testing of the Inner Strength Questionnaire: women living with chronic health conditions. Appl Nurs Res. 2011; 24(3):153–160.

18. Lundman B, Viglund K, Aléx L, Jonsén E, Norberg A, Fischer RS, et al. Development and psychometric properties of the Inner Strength Scale. Int J Nurs Stud. 2011; 48(10):1266–1274.

19. Lundman B, Aléx L, Jonsén E, Norberg A, Nygren B, Fischer RS, et al. Inner strength-A theoretical analysis of salutogenic concepts. Int J Nurs Stud. 2010; 47(2):251–260.

20. Bryant FB, Yarnold PR. Principal components analysis and exploratory and confirmatory factor analysis. In : Grimm LG, Yarnold PR, editors. Reading and understanding multivariate analysis. Washington, DC: American Psychological Association;1995.

21. Vaishnavi S, Connor K, Davidson JR. An abbreviated version of the Connor-Davidson Resilience Scale (CD-RISC), the CD-RISC2: Psychometric properties and applications in psychopharmacological trials. Psychiatry Res. 2007; 152(2):293–297.

22. Jeong HS, Kang I, Namgung E, Im JJ, Jeon Y, Son J, et al. Validation of the Korean version of the Connor–Davidson Resilience Scale-2 in firefighters and rescue workers. Compr Psychiatry. 2015; 59:123–128.

23. Beaton DE, Bombardier C, Guillemin F, Ferraz MB. Guidelines for the process of cross-cultural adaptation of self-report measures. Spine. 2000; 25(24):3186–3191.

24. Polit DF, Beck CT. The content validity index: are you sure you know what's being reported? Critique and recommendations. Res Nurs Health. 2006; 29(5):489–497.

25. Baek HS, Lee KU, Joo EJ, Lee MY, Choi KS. Reliability and validity of the Korean version of the Connor-Davidson Resilience Scale. Psychiatry Investig. 2010; 7(2):109–115.

26. Lynn MR. Determination and quantification of content validity. Nurs Res. 1986; 35(6):382–386.

27. Harrington D. Confirmatory Factor Analysis.(Pocket Guides to Social Work Research Methods Series). New York: Oxford University Press;2009.

28. Davidson J, Connor K. Connor-Davidson Resilience Scale (CD-RISC) manual. unpublished: CD-RICS;2015.

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