심장수술 시 농축적혈구, 자가수혈기 혈액, 체외 순환기 혈액에서의 유리 혈색소 농도 비교

송장호,구승우,백종화,정용보,이정순,최인철 대한마취과학회 2002 Korean Journal of Anesthesiology Vol.43 No.5

Background: Intraoperative autotransfusion or residual blood in a cardiopulmonaty bypass (CPB) circuit has been used to reduce the need for an homologous blood transfutsion during cardiac surgery. However, it may contain some free hemoglobin released from damaged cells. The load of blood containing free hemoglobin may cause renal dysfunction. We measured the amount of free hemoglobin in backed blood, cell saver blood and CPB blood to evaluate what is the least hemolytic blood transfused in cardiac surgery. Methods: This study was performed in 20 patients undergoing cardiac surgery. In each patient, the banked blood, intraoperative salvaged blood with a cell saver and CPB residual blood were sampled at the end of the operation. The concentration of free hemoglobin, hemoglobin and platelet counts were measured in these blood samples and percent of hemolysis was calculated (%hemolysis = [free hemoglobin] / .free hemogloben + hemoglobin]) Results: In salvaged blood with a cell saver, CPB residual blood and banked blood, hemoglobin concentrations were 20.1 ± 2.7 g/dl, 8.0 ± 1.1 g/dl, and 22.2 ± 2.7 g/dl, respectively. Free hemoglobin concentrations were 336.6 ± 239.5 mg/dl, 49.2 ± 26.8 mg/dl, and 279.5 ± 167.5 mg/dl respectively. Platelet counts were 26.1 ± 22.2 × 10^3/mm^3, 116.8 ± 56.5 × 10^3/mm^3, and 94.9 ± 43.6 × 10^3/mm^3 respectively. % Hemolysis were 1.6 ± 1.1%, 0.6 ± 0.4%, and 1.2 ± 0.7% respectively. In the comparison between the salvaged blood with a cell saver and CPB residual blood, free hemoglobin concentration, % hemolysis, and platelet counts had positive correlations (r = 0.8, 0.7, and 0.6). Conclusions: In twenty cardiac surgeries, CPB residual blood had a lower free hemoglobin level than the other two blood groups. The platelet counts in CPB residual blood were higher than those in cell saver blood but did not differ from those in banked blood. Therefore, CPB residual blood was the least hemolytic blood among the three blood groups when a transfusion was performed in cardiac surgery. (Korean J Acesthesiol 2002; 43: 588~593)

國民學校 및 中學校의 科學科 敎育課程의 系列性에 關한 硏究(物理科學分野)

宋寅命,禹榮均,金千中 공주대학교 사범대학 과학교육연구소 1976 과학교육연구 Vol.8 No.1

The results of the examination for the new science curriculum shows that the selection and arrangement of the contents of the teaching subjects is reasonable, but that the contents is difficult and the quantity of the subjects is abandant in both side of teaching and learning is dominant opinion. The results of the sequence analysis of the teaching contents are as follows: (1) the selection of the fundamental concepts, the level of teaching in primary and junior high school, and the sequence of the contents are of no gross faults. (2) The sequence of the "Waves" included the properties of light is cut off, because they do not deal with the waves in the energy concept in junior high school. (3) The unit, "Magnetic Effect of a Current" is dealt with in interaction unit in primary school, and on the other hand it is dealt with in energy unit in junior high school. So, there is room for examination in magnetic effect of current from a viewpoint of the concept development and sequence maintenance. Next, we discussed the theoretical background for the formation of sequence and especially have set up the hierarchy of the inquiring process, in the viewpoint of organizing the contents and techniques dealt with in inquiring activities. And, on the basis of a survey of public opinion, analysis of sequences, and general theory of formation of sequence, we proposed the general rule for organizing the sequence of the concepts and the process-skills between the primary and the junior high school, and for organizing the sequence of the seience curriculum in itself. On the basis of these discussion, we have selected some unit and framed the teaching programme which will serve as a good reference to the practical teaching. We hope that a large number of teachers put the contents proposed in this paper and teaching programme organized process-skills into practical use, and they research and practice the various teaching techniques continuously in order to reach to educational purpose of the new science curriculum.

개화기 남녀 수신교과서의 지향점 분석

송인자 이화여자대학교 한국문화연구원 2007 한국문화연구 Vol.13 No.-

This research attempts to analyze the textbooks of ethics used in educationalinstitutes in the enlightenment period. Therefore, founding purpose of educationalinstitutes as well as textbooks of ethics are examined in terms of virtue ofindividual, family, national society and international relationship . Newly established educational institutes in the enlightenment period in Koreawas established in accordance with 'recover national right movement'. For malestudents, it is focused to obtain the full ability of important task for nation;while for female students, it is emphasized to contribute to the country byraising patriotic children and running the family properly. This gender-biasedfounding purpose was reflected directly to the textbooks of ethics. In thetextbooks, gender role was clearly shown. A man carried out his role in thepublic and productive sphere;in contrast, a woman played her role in theprivate and reproductive sphere. Even the society is in the middle of change,due to the retained men-centered patriarchy, gender role still impliedmen-centered value system and consequently it was being reproduced throughoutthe school education. This research tries to understand the relationships between gender role, schooleducation and textbooks of ethics in the social change of the enlightenmentperiod. Also, this research tries to contribute to analyzing education in theenlightenment period from gender perspective and finally to suggest future-forwarding gender-equal educational alternatives. 이 연구는 개화기 신교육기관에서 사용된 수신서에서 지향하는 덕목을 통하여 교육이 지향하는 이상적 인간상이 어떻게 규정되어 있는지를 이해하기 위한 것이다. 이를 위하여 개화기 신교육기관의 설립이념과 학교교육에 사용된 남녀학생용 수신서를 개인과 가정, 국가사회의 덕목으로 나누어 살펴보았다. 개화기의 신교육기관은 국권회복운동의 차원에서 설립된 것으로 남학생은 국권회복운동의 전면에 나서서 중요한 역할을 할 수 있는 역량을 함양하는 것에, 여학생은 가정교육의 담당자로서 애국적 인재를 기르는 어머니로서, 가정을 잘 경영함으로써 국가발전에 간접적으로 기여하는 역할수행에 필요한 교육을 강조하고 있다. 이는 교과서 특히 수신서에도 그대로 반영되어 공적 ·생산적 영역의역할을 수행하는 남성, 사적·재생산적 영역의 역할을 수행하는 여성이라는 성역할의식이 강하게 드러나고 있다. 이러한 논의를 통하여 개화기 사회변화 속에서 성역할의 변화와 학교교육, 수신서의 역할을 관련지어 이해할 수 있을 것이며 개화기 교육의 다양한 현상을 이해하는 한편, 미래지향적 교육적 대안을 모색하는데 시사점을 얻을 수 있을 것이다

韓國에 있어서 肝吸蟲症 分布에 관한 疫學的 硏究

宋寅喆,李駿商,林漢鐘 고려대학교 의과대학 1983 고려대 의대 잡지 Vol.20 No.1

Korea, a total number of 19,758 stool specimens were collected from the inhabitants who lived in the basins of main 6 rivers, i.e. the Han River, the Gum River, the Nakdong River, the Mangyong River, the Yongsan River and the Seomjin River. The specimens were examined both by cellophane thick smear method and Stoll's egg counting technique during the period from March 1973 to October 1982. The distribution and infection rates were compared in those of river and non-river sides, and the epidemiological statrs was analysed statistically by the regression equations and catalytic curves with the results obtained from two endemic areas. The results are as follows: 1. High egg positive rates were revealed among the inhabitants in the areas of all above river basins, whereas low egg positive rates were obtained among the inhabitants in the areas apart from the riversides. However, in some areas which are not directly connected with the rivers, relatively high rates of Clonorchis infection were also observed. 2. The infection rates of Clonorchis sinensis by sex age were shown significantly different among the population in the most of these studied areas. The rates for males were significantly higher than that for females, and the rates were increased by the higher age groups up to 40 to 59 years old. However in the high endemic areas such as Kimhae the infection rates of both sexes were almost parallel and practically similar high rates revealed in all age groups for 20 to 60 years old. 3. The mean E.P.G. count of Clonorchis infection in the surveyed areas was found higher in the areas which shown as higher infection rates. The degree of the intensity of Clonorchis infection by E,P.G. counts was evenly distributed to heavy and very heavy infections as well light and moderate infections in the areas showed high infection rates. 4. The intensity of endemicity in all surveyed areas was compared with the regression equations calculated with the cumulative percentages of E.P.G. counts. 5. For the quantitative analysis of epidemiology of clonorchiasis in Kimhae and Pyongtrek areas, special type of simple catalytic model was applied to the age prevalence rates revealed through stool examination for Clonorchis eggs and intradermal test for the detection of positive reactors. 6. It was suggested that the two-stage catalytic was well fitted to the prevalince rates by sex and age in the egg positive cases in Kimhae and Pyongtaek areas, and the calculation lead to the equation y=1.042(e-^(0.003t)-e^(-0.074t), a=0.074〉b=0.003 in Kimhae area, and y=1.412(e^(-0.024t)-e^(-0.041t), a=0.024〈b=0.041 in Pyongtaed area. 7. In the high endemic area such as Kimhae, the tendency of familial aggregation was not recognized by statistical analysis. In this area, the mean E.P.C. obtained from same persons in 1973 were compared and descussed statistically.

급성 SO_2중독이 임신흰쥐 및 태자간에 미치는 영향에 관한 조직화학적 연구

송인문,유진화,한갑수 慶熙大學校 1989 論文集 Vol.18 No.-

The purpose of present study was to clarify the effect of sulfur dioxide exposure on enzymatic activities of the liver in pregnant and fetal rats by histochemical method. Female pregnant rats (Sprague-Dawley strain) were used in this study. The animals were exposed to 50ppm SO_2 in gas. chamber for 5 minutes, 15 minutes, 30 minutes and 60 minutes and were sacrificed on 17 days, 19 days and full term of gestation period and fetal liver were taken. The changes of enzymatic activities of cytochrome oxidase, acid phosphatase, alkaline phosphatase and lactate dehydrogenase were observed by histochemical stainings. Significant data have been summarized as follows; 1. In the pregnant rat, 19th fetal rat and full term fetal rat, the enzymatic activities of cytochrome oxidase and lactate dehydrogenase of SO_2 exposure group decreased in comparison with the control group. 2. In the pregnant rat, 19th fetal rat and full term fetal rat, the enzymatic activities of acid phosphatase of SO_2 exposure group increased in comparison with the control group. But alkaline phosphatase has showed a no significant changes in comparison with the control group. 3. In the 17th fetal rat, the changes of enzymatic activities of cytochrome oxidase and lactate dehydrogenase of SO_2 exposed liver showed a mild positive activity as it was in the control group. However, acid phosphatase activities has showed a negative activity in the both group. 4. The enzymatic activities of cytochrome oxidase, acid phosphatase, alkaline phosphatase and lactate dehydrogenase of SO_2 exposed liver showed a significant changes in the pregnant rat in comparison with the fetal rat.

35세 이하에서의 결장 및 직장암 환자에 대한 임상적 고찰

송인철,윤충,이행철,이양삼 대한대장항문학회 1996 Annals of Coloproctolgy Vol.12 No.3

自我槪念형성에 미치는 敎師의 영향

송인섭 숙명여자대학교 사회·교육과학연구소 2002 사회 교육과학연구 Vol.5 No.2

Children bearing first names judged desirable by teachers tend to have more positive self concepts (Garwood, 1976). First names were also found to lead to (lifferem teacher expectations so that name stereotyping plays some role in the classroom. Other studies by Parlady (969) and Rubovits and Maehr (973) confirm the expectancy effect. Coopersmith's (967) study also showed that parents who expected their children to live up to the standards they established were more likely to encourage healthy self esteem in their offspring than parents who did not have these expectations. From the work of Shaw and Dutton (962) it would appear that parents of under-achieving children have more strongly negative attitudes towards their children than do the parents of achieving youngsters. However, the study docs not reveal definitely whether these attitudes arc one of the results of under-achievement, or one of its cause. From a logical point of view, it is easier to build a case for such attitudes as casual rather than resultant factors. This finding was particularly marked for boys. Thus, many under-achievers start school under a handicap and simply justify their parents' expectations. The strong grip of constant demeaning squeezes out the last drops of self confidence and worth. Expectations represent a belief in the pupils' competency and ability. When established at reasonable levels they provide a vote of confidence out of which positive self esteem can grow. Teachers apparently tend to interact more positively and favorably with 'brighter' children, and the latter respond by being more effective pupils, thus confirming the teachers' expectations. Pupils reputations arc notorious for being passed on from one teacher to another, increasingly determining the child's performance for good or bad. 'Watch him, don't turn your back on him, he's up to all sorts of tricks', to 'He's a hard worker, you'll always get good worker from him', are typical of the staftroom comments heard in every school. Non-verbal communication by facial expression, tone of voice and gaze direction also communication expectations. Considerable research indicates, too, that children will work harder at tasks and are thereby more likely to achieve a positive self-concept if they believe that they, rather than chance or the teacher, are responsible for the successes they achieve (Rotter, 1966). In fact, a large-scale national survey indicated that a pupil's belief is his control over his destiny was more important to achievement than any other school factors measured, such as facilities, teachers and curriculum (Coleman, 1966). This concept of external locus of control was briefly noted in Chapter 8, section F(a) The three conditions which facilitate the high self esteem in the home environment (Ch.7). These three are: 1. The teacher's acceptance of the child, while at the same time recognizing the child's strengths, problems and limitations. By accepting the child the teacher indicates that the child is worthy of the teacher's attention and respect. This respect enables the child to come to terms with his abilities and limitations. 2. The existence of explicit limits, clearly defined and consistently enforced, which provide standards of conduct and behavioral expectations. 3. The provision of respectful treatment which is given to pupils who observe limits and act in accordance with rules and guidelines of the classroom. As we shall see later in this chapter, the ability of the teacher to provide these conditioning depends quite markedly on the teacher himself possessing a positive self-concept. This allows him to function in a competent confident way able to accept all pupils as individuals in a supportive environment providing clear and realistic expectations at an individual level. Another line of attack to improve pupil self-concept is by direct counselling, which in reality provides the same sort of conditions noted above, i.e. acceptance, respect, limits in a supportive rriilieu, but undertaken in a more sophisticated and planned way. 교사와 학생의 만남은 교사의 일반적 조망과 生의 철학에 의해서 교사에게 침투된다. 교사의 자신과 타인을 향한 태도는 교실 내에서의 대인관계 행동과 수업형태에 중요한 영향을 미친다. 긍정적 자아개념과 타인에 대한 긍정적 개념은 상관이 있다. 긍정적 자아개념은 타인과 친애적이고, 지지적인 관계형성을 촉진한다. 학생들이 그들을 향한 교사의 느낌을 정확히 평가할 수 있고, 교사를 친애적으로 평가한 학생들은 긍정적 자아개념을 형성한 학생들임을 증명하였다. 교사의 언어사용이 학생의 자아개념을 고양시킬 수 있음을 나타냈다. 敎授實際에서 높은 점수를 기록한 교사는 낮은 점수를 기록한 교사보다 자아개념이 현저히 높다. 敎授에서의 성공은 긍정적 자아개념, 자신감, 적응과 확실히 밀접한 관계가 있다.

Association of HLA-DRB1 and -DQB1 Alleles with Susceptibility to IgA Nephropathy in Korean Patients

In Ji Won,Jung Kiwook,Shin Sue,Park Kyoung Un,Lee Hajeong,Song Eun Young 대한진단검사의학회 2022 Annals of Laboratory Medicine Vol.42 No.1

Background: Associations between IgA nephropathy (IgAN) and HLA-DRB1 and -DQB1 alleles have been reported in several ethnic groups. We investigated the association of HLA-DRB1 and -DQB1 alleles with the predisposition for IgAN and disease progression to end-stage kidney disease (ESKD) in Korean patients. Methods: We analyzed HLA-DRB1 and -DQB1 genotypes in 399 IgAN patients between January 2000 and January 2019 using a LIFECODES sequence-specific oligonucleotide (SSO) typing kit (Immucor, Stamford, CT, USA) or a LABType SSO Typing Test (One Lambda, Canoga Park, CA, USA). Alleles with a significant difference in two-digit resolution were further analyzed using in-house sequence-based typing and sequence-specific primer PCR. As controls, 613 healthy hematopoietic stem cell donors were included. Kidney survival was analyzed in 281 IgAN patients with available clinical and laboratory data using Cox regression analysis. Where needed, P-values were adjusted using Bonferroni correction. Results: The allele frequencies of HLA-DRB1*04:05 (corrected P [Pc]<0.001), -DQB1 *04:01 (Pc=0.048), and -DQB1*03:02 (Pc=0.021) were significantly higher in IgAN patients than in controls, whereas those of HLA-DRB1*07:01, -DRB1*15:01, -DQB1*02:02, and -DQB1*06:02 (Pc<0.001 for all) were significantly lower in IgAN patients than in controls. The allele frequency of HLA-DQB1*05:03 (Pc=0.016) was significantly lower in the ESKD group than in the non-ESKD group; however, there was no significant difference for ESKD progression between these groups. Conclusions: We report novel associations of HLA-DRB1*15:01, DQB1*02:02, -DQB1*03:02, and -DQB1*04:01 with IgAN. Further studies of HLA alleles associated with IgAN progression in a larger cohort and in various ethnic groups are needed.

Concurrent Chemoradiation Therapy in Stage Ⅲ Non-small Cell Lung Cancer

Song, Jung Sub,Jang, Jie Young,Shinn, Kyung Sub,Lee, Sun Hee,Choi, Ihl Bhong,Kim, In Ah,Kang, Ki Mun,Park, Jae Gil,Kuak, Mun Sub THE CATHOLIC UNIVERSITY OF KOREA 1997 Bulletin of The Catholic Research Institutes of Me Vol.25 No.-

This study was tried to evaluate the potential benefits of concurrent chemoradiation therapy(low dose daily cisplatin combined with split course radiation therapy) compared with conventional radiation therapy alone in stage Ⅲ non-small cell lung cancer. The end points of analyses were response rate, overall survival, survival without locoregional failure, survival without distant metastasis, prognostic factors affecting survival and treatment related toxicities. Between April 1992 and March 1994, 32 patients who had stage Ⅲ non-small cell lung cancer were treated with concurrent chemoradiation therapy. Radiation therapy for 2 weeks (300 cGy given 10 times up to 3000 cGy) followed by a 3 weeks rest period and then radiation therapy for 2 more weeks(250 cGy given 10 times up to 2500 cGy) was combined with 6㎎/M^2 of cisplatin. Follow-up period ranged from 13 months to 48 months with median of 24 months. Historical control group consisted of 32 patients who had stage Ⅲ non-small cell lung cancer were received conventionally fractionated(daily 170-200 cGy) radiation therapy alone. Total radiation dose ranged from 5580 cGy to 7000 cGy with median of 5940 cGy. Follow-up period ranged from 36 months to 105 months with median of 62 months. Complete reponse rate was higher in chemoradiation therapy(CRT) group than radiation thernpy(RT) group(18.8% vs. 6.3%). CRT group showed lower in-field failure rate compared with RT group(25% vs. 47%). The overall survival rate and no significant differences in between CRT group and RT group(17.5% vs. 9.4% at 2 years). The survival without locoregional failure (16.5% vs. 5.3% at 2 years) and survival without distant metastasis(17% vs. 4.6% at 3 years) also had no significant differences. In subgroup analyses for patients with good performance status(Karnofsky performance scale≥80), CRT group showed significantly higher overall survival rate compared with RT group(62.5% vs. 15.6% at 2 years). The prognostic factors affecting survival rate were performance status and pathologic subtype(sqamous cell cancer vs. nonsquamous cell cancer) in CRT group. In RT alone group, performance status and stage (Ⅲa vs. Ⅲb) were identified as a prognostic factors. RTOG/EORTC grade 2-3 nausea and vomiting(22% vs. 6%) and bone marrow toxicities(25% vs. 15.6%) were significantly higher in CRT group compared with RT alone group. The incidence of RTOG/EORTC grade 3-4 pulmonary toxicity had no significant differences in between CRT group and RT group(16% vs. 6%). The incidence of WHO grade 3-4 pulmonary fibrosis also had no significant differences in both group(38% vs. 25%). In analyses for relationship of field size and pulmonary toxicity, the patients who treated with field size beyond 200㎠ had significantly higher rates of pulmonary toxicities. Conclusions: The CRT group showed significantly higher local control rate than RT group. There were no significant differences of survival rate in between two groups. The subgroup of patients who had good performance status showed higher overall survival rate in CRT group than RT group. In spite of higher incidence of acute toxicities with concurrent chemoradiation therapy, the survival gain in subgroup of patients with good performance status were encouraging. CRT group showed higher rate of early death within 1 year, higher 2 year survival rate compared with RT group. Therefore, to evaluate the accurate effect on survival of con- current chemoradiation therapy, systematic follow-up for long termsurvivors are needed.

자아개념의 多元性과 학업성취간 관계

송인섭 숙명여자대학교 사회 교육과학연구소 2001 사회 교육과학연구 Vol.5 No.1

Wylie는 “성취와 능력이 성취와 능력자아개념들, 그리고 일반 존중감과도 강하게 관계될 것”이라고 가장했다(1979, 355). 본 절은 목적은 이러한 연구를 간략하게 논평하는 것이다. Shavelson과 동료들의 모형에서 학문적 자아개념은 일반 자아개념의 한 요소이며, 수학과 언어와 같은 특정내용 분야에의 자아개념으로 나뉘어진다. SDQ 해석에 대한 구인타당도와 Shavelson 등의 모형의 구인타당도에 대한 지지는 ① 학업성취가 비학문적 혹은 일반 자아개념보다는 보다 긍정적으로 학문적 자아개념과 상관된다. 그리고 ② 언어와 수학성취들은 자아개념의 다른 특성보다 그 분야의 자아개념과 더 높게 상관되어야 할 필요가 있다. Educators have been critically concerned with the question of whether increasing self-concept changes achievement, or increasing achievement changes self-concept. Before the question of “which causes which” can be answered, however, it is necessary to fist establish covariation between these two variables. As Mill(1869) argued, covariation is the first important criterion for inferring cause. The other criteria are the temporal precedence of the cause, and that other explanations of the cause and effect relationship must be eliminated(see also Cook & Campbell, 1979; Kenny, 1979) The Three Criteria The meta-analysis just discussed indicated that, on average, only 2% to 4% covariation between self-concept and achievement can be expected. Thus, it is extremely difficult to go further and investigate causal claims. Kenny(1979 p.238) noted that variables with low correlations―he said less than .3―typically yield disappointing and confusing results with respect to causality. Thus any research assessing causality needs to pay careful attention to the first criteria; that is, the amount of covariation between the two variables. Byrne(1986), for examples, in a very elaborate study using causal modeling, was not able to establish causal pre dominance of self-concept of achievement. This is not surprising, given that the average covariance in her study between general self-concept and academic achievement was 4%. Pottenbaum, Keit, & Ehly (1986) did not find either self-concept or achievement causally dominant, and their average covariation was 1%. Marayuma, Rubin & Kingsbury (1981) reported a similar conclusion. Their average covariance was 4%. Skaalvik & Hagtvet (1990) found that academic achievement seems to have causal predominance over self-concept of ability in one of their samples, and academic achievement have causal predominance over global self-concept in the other(but there were no relations between achievement and self-concept of ability). These seemingly conflicting findings are based on an average 3% to 10% covariation. Moyer(1979) argued that self-concept is causally dominant but noted that the correlations between self-concept and achievement are “generally quite weak”(r<.20) Wattenberg and Clifford (1964) were more definite: “Even as early as kindergarten, self-concept phenomena are antecedents and predictors of reading accomplishments” (p.461). There conclusions are strong, but are actually based on finding that only 10 of 28 correlations were positive, none were significant, and overall the correlations between reading and changes in self-concept were “slightly inclined to be negative.” Such findings are hardly convincing. Given the low percentage of covariation, it is not surprising that there are just as many studies supporting the precedence of self-concept over achievement (Byrne, 1986, cited 8) as there are for the opposite case (Byrne cited 6). Higher correlations are reported between academic achievement and self-concept of ability, and typically these studies report predominance of achievement over self-concept of ability. An alternative explanation to this causal predominance is that academic self-concept measures self-estimates of ability. As noted in chapter 5, the widely used Brookover test very much involves a self-estimates of ability, has no items relating to the saliency of achievement, and has only one item relation to satisfaction. It was, therefore, not surprising that achievement was a better predictor of self-estimates of achievement than vice versa. For example, Marsh(1990a) re-analyzed the Bachman(1970) and Bachman & O'Malley 1997, 1986) data based on 1,456 students retested at 10th, 11th, 12th, and one year after graduation. There was support for the effects of prior self-concept of ability on subsequent reported grade, and no significant relationships in the other direction. The second criterion relates to the temporal issue. Before self-concept can be said to cause changes in achievement, programs to change self-concept must precede changes in achievement (or vice versa). In the social sciences these claims are difficult to test as the choice of the time interval is tricky. It may not be evident. If on the other hand, the time interval is too long than a premature measure of achievement may not detect the changes in achievement. Further, delayed cause are les likely to be solely attributable to the anticipated effect. Of course, self-concept and achievement are not static, and there may be much feedback between the two variables. Thus, any model that claims that changes in self-concept lead to changes in academic achievement (or vice versa) must distinguish between recursive (self-concept causes achievement or achievement cause self-concept) and nonrecursive theories (self-concept and achievement affect each other). There may be a feedback look between the two variables so that changing one has “instantaneous” effects on the other, and so on. Given that the covariation is so small, it would be extremely difficult to design an experiment to test a recursive versus a non-recursive model. The third criterion is that other explanations of the cause and effect relationship need to be eliminated. There can be many reasonable alternative rival hypotheses that could account for any changes in achievement following a self-concept program (or vice versa). O'Malley and Bachman(1976) concluded that much of the correlation between self-concept and achievement an best be explained “as reflecting a common set of prior cause background, ability and earlier scholastic success” (p.38). Marayuma, Rubin, and Kingsbury (1981) argued that self-concept and achievement are related “only insofar as they shared the background variables of social class and academic ability as common causes” (p.973). Moreover, self-concept may moderate self-efficacy or expectations about achievement. Alternatively, high achievement may lead to a more realistic understanding of expectation, which, when these expectations are met, may lead to an increased level of self-concept (see Ames, 1978; Sharp & Muller, 1978). A causal model that does not allow for such intervening variables would thus be flawed. There may be many variables that similarly moderate the relationship between self-concept and achievement. Calsyn and Kenny (1977) found more support for a causal precedence of achievement over self-concept for females that for males. This, they argued, was possibly because females are more sensive to feedback (see also Bridgeman & Shipman, 1978; and for an opposite conclusion regarding sex differences and causal dominance see Midkiff, Burke, Hunt & Ellison, 1986). Song and Hattie (1984) also investigated the moderating effects of home environment (but also see Chapman, Lambourne, & Silva, 1990). Other moderators that have been suggested include race, age, and ability (Bachman & O'Malley, 1977). Any research study that investigates the causal relationship between self-concept and achievement also may well consider multiple causes. Increasing self-concept and some other variables, such as increased teacher understanding of the mechanisms for change, may lead to increased achievement.